Basics Series: How to make Italian Meringue Buttercream

Today we’re going to learn about Italian Meringue Buttercream (IMBC)

This is the most DELICIOUS icing and the only thing I use to ice cupcakes and cakes with.

I originally found my recipe/tutorial online from Warren Brown, but have adapted it a little and worked out how to make it without the need for a sugar thermometer. Jackpot!! :-)

It does initially seem like a lot of work, but once you get things mixing, you can leave your mixer for a while and get a few other bits and pieces done in the meantime. The more you make it… the easier it gets and trust me… nothing is nicer than this!!!!!

The most important thing to remember with this recipe is that the butter needs to be the same temperature as the meringue mixture when you add it. If not.. the mixture will curdle.

In winter I find that I need to zap the butter in the microwave for a few seconds and my meringue mixture easily takes 10 minutes to reach room temperature.

Variations on this recipe are:

Caramel – bring to the boil 150g Brown sugar, 150ml Cream and 50g Butter.  Simmer 5 minutes before setting aside to cool down and thicken up. Add to your IMBC once it has cooled down.

Lemon – make up half a batch of this lemon curd and add to your IMBC once it has cooled down.

Raspberry – make up half a batch of this raspberry curd (but strain out the seeds!), and add to your IMBC once it has cooled down.

Chocolate – mix in 3-6 tablespoons of cooled down chocolate ganache (Ganache being at a ratio of 2:1 dark chocolate:cream)

IMBC can be made an stored at room temperature for 3 days, or in the fridge for 7-10 days or you can freeze it. You will need to rewhip the IMBC if it is in the fridge/freezer or during winter months. Obviously, if it’s a stinking hot day, don’t leave your IMBC at room temperature :-)

Personally, I prefer to make it fresh and I whip it up on the day I’m icing my cupcakes or filling my cake.

I’ve prepared a video about making the IMBC as I think it’s easier to understand exactly how to make it. Quite clearly there was no budget allocated to video production or makeup :-) so bear with me!!!! It was also filmed over one night and morning.. hence the screaming kids in one segment, and on reflection my voice sounds HORRIBLE over the top of the mixer!! :-) (must be what I sound like to my kids all day!)

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72 Responses to Basics Series: How to make Italian Meringue Buttercream

  1. Anne-Marie April 27, 2012 at 12:56 pm #

    Awesome! i made this for the first time this week after reading about it on your blog and watching the video :) Was so yummy! (i had to go hunting for a candy thermometer though!) I was surprised how hard it set overnight.. is that normal?

    • BronnieBakes Admin April 27, 2012 at 2:24 pm #

      Did you leave it at room temp or in the fridge? It will set hard in the fridge and sometimes at room temperature (depending on the temp!). You can always re-whip it if you need to pipe it the next day.

      Glad you gave it a try!!!!

      x

      • Anne-Marie April 27, 2012 at 8:31 pm #

        I refrigerated it.. was on a cake :) was surprisingly easy following the instruction on the video you posted. :) i nearly didn’t try because so many people said its so hard but was impressed and it was delicious! Will attempt piping next time!

        • BronnieBakes Admin April 28, 2012 at 5:27 am #

          Yes – definitely give piping a go!!!! It’s lots of fun
          xx

  2. Paula April 28, 2012 at 5:11 am #

    Love Italian Meringue Buttercream. Good video tutorial. I always rely on my thermometer though. Don’t trust myself without it :)

  3. Amanda W April 28, 2012 at 7:45 am #

    I’ve tried making this before and it was a disaster but I think I might try to give it another go :)

  4. Jacinta Perkins May 1, 2012 at 10:33 am #

    Bronnie this video is fantastic and I’m dying to try it. You explain things wonderfully and I’m sure it would taste incredible. Can you make IMBC in advance? How long will it keep and will it freeze? Thank you so much for your sharing!

    • BronnieBakes Admin May 1, 2012 at 10:57 am #

      Hi Jacinta :-)

      Thankyou so much for your lovely comments – I really appreciate it! I should have included all of that information in the tutorial, so I’ve just edited it for you, but you can definitely make it in advance!

      xx

      • Jacinta Perkins May 1, 2012 at 12:53 pm #

        Thank you so much Bronnie, I am new to cake making and am overwhelmed by how generous everyone is with sharing information. Thanks again for the tute and the info on how to store it. Have a great day

  5. Amanda July 15, 2012 at 10:51 pm #

    Hi Bronnie,

    I just tried the buttercream but it went wrong :(
    I don’t think I left it til it was cool enough before I added the butter so it was really quite runny. It set up a little in the fridge, but it still isn’t piping consistency. Do you think that is where I went wrong?

    Amanda

    • BronnieBakes Admin July 16, 2012 at 11:43 am #

      Hi Amanda

      I’m so sorry to hear that your IMBC didn’t work out! How long did you beat it for after adding the butter? It does start out running as the fat and meringue start to mix, but it then thickens up. The trick is that the butter needs to be the same temperature as the meringue… so in winter I find I usually need to zap the butter in the microwave for 10 seconds.

      My meringue takes about 10 minutes to beat until it hits room temperature.

      x

  6. Stephanie September 5, 2012 at 10:19 am #

    Hi Bronnie,

    I followed this tutorial and made my first batch of Italian meringue buttercream. It worked out well. I don’t need it for a couple of days, but thought I should try now in case it didn’t work…. Will i need to re-whip if it stays at room temp for 2 days?

    Thank you.

    • BronnieBakes Admin September 5, 2012 at 11:06 am #

      Hi Stephanie

      Glad to hear you tried the IMBC :-)

      It will depend on the room temperature, but most likely yes, you will need to whip it!

      x

  7. Peta September 8, 2012 at 8:45 pm #

    Hi Bronnie
    Thanks so much for your tutorials!
    I made the very hungry caterpillar cake topper for my son’s 1st birthday today and made a leaf shaped rainbow cake iced with imbc for it to sit on. I’d never heard of the italian meringue buttercream before this week, but you made it do easy!
    Thanks again!

    • BronnieBakes Admin September 10, 2012 at 11:43 am #

      oh that’s fantastic Peta! Well done! I’m so glad you tried the IMBC and the tutorials were helpful :)

      xx

  8. Christine Schafer September 29, 2012 at 4:39 pm #

    Oh Bron thanks so much for this tute!!! It is idiot proof which is exactly what I needed. Your icing is DELICIOUS!!!!!!!! I just made my first batch and it turned out so well. I love it, you rock!!

    Chris x

    • BronnieBakes Admin September 29, 2012 at 9:56 pm #

      yay!!!! so glad it worked well for you xxxx

  9. Alison October 6, 2012 at 3:00 pm #

    Can you tell me how many cups if IMBC this makes? I need to pipe swirls on 24 cupcakes – would this be about as much as I need?

    Thanks

    Alison

    • BronnieBakes Admin October 6, 2012 at 3:13 pm #

      Hi Alison

      Good question :-)

      It really depends on how high your swirls are! It will make a decent bowl of icing and I can get at least 24 swirls out of a mixture, but I don’t do the full ‘icecream cone’ swirls on mine.

      x

  10. Alison October 8, 2012 at 4:50 pm #

    Thanks for that great tutorial! I have never been game to try this before as everyone says it is too tricky and you need a thermometer, and it has to be timed to perfection etc. I just did what you did in the video and wow – my gorgeous IMBC is resting on the bench. I plan to use it tomorrow night so it wil be in fridge soon.

    Just a tip you might find helpful – you mention in the video that if you get a bit of shell or yolk etc in the whites you need to start again. Next time this happens just pick up an egg shell and use it as a scoop. Works every time but it is just about impossible with a spoon! Try it and you will be pleasantly surprised.

    • BronnieBakes Admin October 8, 2012 at 5:14 pm #

      THankyou Alison – that is a fantastic tip!!! I am always getting egg shell in my mixture, so I will try that next time.

      I’m so glad you gave the IMBC a try. I’m a little obsessed with it (in case you couldn’t tell) and make it all the time!!

      xx

  11. alison October 10, 2012 at 2:41 pm #

    Sorry to keep popping back with things! My IMBC was so fluffy and white when I made it. I covered it and put it into the fridge overnight. Whipped it up the next day and before my eyes the volume went down to about half and it separated a little. I kept whipping and whipping and it came back together, but quite yellow and not nearly as much.

    Any suggestions of what to do – sometimes we just can’t make and use things the same day when we are working etc. Would appreciate your input.

    Alison

    • BronnieBakes Admin October 10, 2012 at 6:13 pm #

      Hi Alison

      No problem at all with the questions :-)

      Try whip

    • BronnieBakes Admin October 10, 2012 at 6:14 pm #

      Hi Alison

      No problem at all with the questions :-)

      Try whipping it up and using a hot cloth around the bowl – that will help bring it together. I keep my IMBC on the bench at room temperature when it’s not too hot as it will keep for 3 days on the bench. But you will lose some volume if you have to rewhip it – but the hot cloth should help. I use a chux cloth and just keep running it under hot water and then placing it around the bowl… maybe do it about 8 times or so.

      Let me know how you go!

      x

  12. Linda October 10, 2012 at 3:19 pm #

    Bronnie, thankyou so much. I made my first attempt a italian meringue buttercream last night after days of online research and trepidation. Your video was so inspiring and so helpful, since I don’t have a sugar thermometer. I was thrilled with the resulting frosting, so smooth and tasty, perfect texture and looks gorgeous. I appreciate your help, cheers, Linda

    • BronnieBakes Admin October 10, 2012 at 6:10 pm #

      oh thankyou Linda for your lovely comment :-)

      I’m so glad everything worked out well – isn’t it so delicious?!!!! You’ll have to add some flavouring in next time!

      xxx

  13. Belinda Mathson October 14, 2012 at 12:55 pm #

    Hi Bronnie, I am really excited to try your recipe! It looks easy on your video. I just hope it comes out well. I have a few questions. First, I am making a three tier cake with the ombre ruffles for a birthday party on Friday. Do you think I should bake the cake on Monday? Leave it in the fridge till Wednesday? Make the IMBC on Wednesday and pipe the cake the same day. Can I start decorating the cake with the fondant the same day? Sorry, for a lot of questions. I have done some cakes before but I always want to perfect them! Thanks!

    • BronnieBakes Admin October 14, 2012 at 12:59 pm #

      HI Belinda :-)

      What type of cake are you making? if it is a mud cake then yes, make it straight away and put it in the freezer. Otherwise I would bake it Wed night. Thursday morning make the IMBC and fill your cakes, then ganache them and then start with the fondant. Are you doing ruffles for all 3 tiers?

      No problem with the questions – happy to help!

      x

      • Belinda Mathson October 15, 2012 at 4:34 am #

        Thank you for getting back to me. I am just making a regular white cake with just ruffles on the bottom tier. I am going to put white chocolate sea shells around the tier! It’s an under the sea theme birthday party.

        • BronnieBakes Admin October 15, 2012 at 2:07 pm #

          Sounds lovely!

          So, I’d bake, fill and ganache Wednesday and then cover with fondant and decorate thursday so that it’s all ready for friday!

          All the best
          x

  14. Justace Clutter November 19, 2012 at 1:52 pm #

    I have made the basic version of this recipe (without flavoring except for vanilla) several times now and it always comes out great. I do have to put it in the fridge for just a but to help the icing setup and then I take it back to a blender. This time I tried to do the caramel version. It has not turned out so well this time. It seemed that it just would not setup like it normally did and also seems to kind of separate now. When I did the caramel flavoring I used heavy cream. Was that incorrect? Should I have used coffee creamer?

    Thanks for the recipe…

    • BronnieBakes Admin November 19, 2012 at 10:02 pm #

      Hi Justace

      The consistency of the IMBC will change if your flavouring is too runny – was the caramel sauce thick? I just use double cream or whatever the ‘normal’ cream at the supermarket is… but I cook my sauce so that it is quite thick.

      x

      • Justace Clutter November 20, 2012 at 2:16 am #

        Humm, it was pretty runny (the caramel flavoring). The instructions stated to cook it for 5 mins once boiling… Maybe I should have let more of it cook off…

        • BronnieBakes Admin November 21, 2012 at 2:07 pm #

          Did it not thicken once it cooled down?

  15. Jess Thomson November 20, 2012 at 10:02 am #

    Hi Bronnie,

    I am wondering if this is the buttercream you would use if you were to make a cake with buttercream frosting only (no fondant)?

    I am needing to make a cake with buttercream frosting only on the outside and am concerned it will start to yellow before the event!

    Jess

    • BronnieBakes Admin November 21, 2012 at 2:10 pm #

      yes – absolutely Jess! It is the only icing I make and use.

      I haven’t had any problems with it turning yellow – how soon before the event are you going to make and ice the cake??

      x

  16. Jane December 11, 2012 at 5:10 pm #

    Hi Bronnie

    I’m planning on trying this instead of a usual fondant/marzipan covering on my Christmas cake but I have a couple of questions:

    1 – could this IMBC be used with Marzipan or will the oils in it spoil the marzipan?
    2 – what sugar should I use to begin with? Granulated/fine/confectioners?

    Many thanks

    J

    • BronnieBakes Admin December 11, 2012 at 5:25 pm #

      Hi Jane :-)

      I don’t quite understand – do you want to use IMBC under marzipan? or instead of it?

      I would only recommend using it instead of marzipan. I don’t quite know why you’d want it under marzipan??

      The sugar I use is castor sugar which is fine sugar

      Hope that helps!

      x

  17. Jane December 12, 2012 at 1:20 am #

    Hi Bronnie

    Thanks for the advice, sorry to confuse you! I meant could I use it instead of fondant…I don’t like marzipan OR fondant but a lot of my guests really like marzipan so I wondered if I could line my cake with the marzipan and then use the buttercream on top in place if the fondant icing, or if the oils in the butter would spoil the marzipan…

    I think I will just use the buttercream and maybe make some marzipan snowmen for the marzipan fans.

    This is a fantastic site – thanks so much and Merry Christmas

    J x

    • BronnieBakes Admin December 12, 2012 at 1:55 pm #

      Hi Jane

      Ahh.. ok…that makes more sense!!! I don’t think that IMBC over marzipan would work at all – you could either do as you suggested and just have marzipan decorations. Or… you could cover with marzipan and use the IMBC as the filling after cutting the cake into layers.

      Hope that helps!

      x

  18. Mandy April 3, 2013 at 7:38 pm #

    I ever normally dont write on these but OMG, I followed your instruction to the letter and it came out beautifully!! I took the butter and eggs out the night before making it as I think that these both have to Be at the same temperature.

    Also you have to make sure that once you have put the sugar syrup in the bowl it has to cool down to room temperature before putting in the butter which is why some end up like soup! I ended up couple of bags of frozen peas around my mixer whilst it was whisking the meringue til cool…. It took around 18 mins to cool in my k chef…

    This is my first time making it, after reading reviews was a bit worried about doing it but watching this guide you needn’t be, yes you may need a thermometer but after the sugar syrup came to the centre boiling it took 30 seconds to get up to temp so you why bother! 160 degrees

    Anyway sorry for the long post, thank you so much for sharing this,

    M xxx

    • BronnieBakes Admin April 3, 2013 at 8:19 pm #

      yay – thankyou so much for your detailed feedback. I’m so glad you had such success with the IMBC as I absolutely love it!
      :-)

  19. judy April 21, 2013 at 3:40 am #

    I’ve just discovered your site !!!!! Thank you!!! It is loaded with such an abundance of information. I love to bake, and while my sons were growing up I always had someone to eat my creations. I’m an empty-nester now. I’ve done some sugar work for wedding cakes and I’ve been asked to do my Son’s wedding cake next year. They want a small cake for cutting and 150 cupcakes. What is the best icing for the cupcakes?
    I will be experimenting and feeding the people on my street until I get it right. I think with your Tutorials I can pull this off…I’ll keep you posted, thanks

    • BronnieBakes Admin April 22, 2013 at 7:22 am #

      Hi Judy :-)

      Thankyou so much for your lovely comments – I really appreciate them!!

      Once you go further through my site you will find that I am completely obsessed with Italian Meringue Buttercream and talk about how good it is all the time!! I absolutely love it and make it now for everything. Here is a link to my tutorial for this, and you can always add yummy flavourings like lemon curd or chocolate ganache.
      http://bronniebakes.com/2012/04/27/basics-series-how-to-make-italian-meringue-buttercream/

      x

  20. Natalie April 26, 2013 at 10:38 pm #

    Hi Bronnie,

    I am about to attempt IMBC for the first time and found your tutorial very helpful. I have a quick question about the chocolate variation. I usually use pure cream to make ganache. Should I use it for this recipe? Also with using dark chocolate, does it have the bitter taste or does all the sugar in the buttercream sweeten it? I am looking to ice caramel mud cupcakes.

    • BronnieBakes Admin April 28, 2013 at 6:27 pm #

      Good on you for making it Natalie!! It is divine :-)

      I just use regular cream (the cheap aldi brand!) and that is fine. You would be fine just using some melted chocolate – again, I use the cheap aldi cooking chocolate (dark) but just make sure you don’t add it while it’s hot. It definitely doesn’t taste bitter! But It might if you use the high % cocoa chocolate.

      If you are going to ice caramel cupcakes, then I’d suggest you use this recipe http://bronniebakes.com/2011/03/18/how-to-make-the-most-delicious-cake-filling/ it is AMAZING!!!!

      Let me know how you go!!

      x

  21. Eve May 17, 2013 at 4:52 pm #

    Hey! I LOVE your website; I just made the IMBC for a friends birthday cake. It was AMAZING!!!! I made a 2 layer cake, filling and topping it with IMBC and there was still tons of leftovers :) My one little flaw was the consistency; I followed every single direction right, even though I didn’t need a candy thermometer. But, I didn’t have enough butter, so I used some gourmet spereading butter that was cooking butter, but soft (so, not margarine or anything). Mmmm… yeah, it wasn’t the best idea, because it made the IMBC a bit runnier (but still at piping consistency), and it didn’t really harden. It was still great and my friend loved it! Thankyou so much for this inspired site!! :D

    • BronnieBakes Admin May 19, 2013 at 4:49 pm #

      Hi Eve

      Thankyou so much for your lovely comment. I’m SO glad you gave IMBC a try as I absolutely love it! That is a shame about the consistency. I’ve never tried it with anything other than butter, but I do find if my consistency is a little runny that if I put it in the fridge it will harden a little and it is easier to pipe/fill.

      Thanks!
      x

  22. Caterina June 21, 2013 at 8:16 pm #

    Hi bronnie, just wondering if I pipe my cupcakes with Italian buttercream the night before whether they need to go in the fridge or can I leave them out overnight. Thanks Caterina

    • BronnieBakes Admin June 23, 2013 at 9:14 pm #

      Hi Caterina

      You can leave IMBC at room temperature for up to 3 days so they will be fine out overnight. Hope that helps!

      x

  23. Angela August 25, 2013 at 6:35 pm #

    Hi Bronnie,
    Great tutorial! thank you. I have made IMBC before and when i make it and pipe onto cupcakes it looks lovely and white in colour. But the next day it is quite yellow? I’m hoping you may know why….. your advise would be really appreciated :) thank you.
    Angela. :)

    • BronnieBakes Admin August 25, 2013 at 7:10 pm #

      Hi Angela

      I’m sorry – but I’ve never had that problem… or at least it hasn’t changed in colour enough for me to notice!! Sorry I can’t help you with a proper explanation.

      x

  24. Paul October 24, 2013 at 8:01 pm #

    Wow! Making a cake for mother & sister and stumbled across this recipe. Had to try it out as it looked epic. I think I just had a foodgasm!

    5 stars of awesomness!

    • BronnieBakes Admin October 24, 2013 at 8:22 pm #

      Thanks Paul – if you think that is good, you have to try the caramel flavour!!!

  25. Tiff November 16, 2013 at 7:44 am #

    Agreed. Your site is wonderful! Thank you for sharing! Just wondering re freezing your cakes. Do you take them out of the tins, weap the cake in plastic, put back in the tins then freeze?

    • BronnieBakes Admin November 16, 2013 at 11:54 am #

      Thankyou Tiff for your lovely comment! I really appreciate it :-)

      Once i bake my cake I brush the top with boiling hot water and cover with foil and leave overnight until cold. Then I take it out of the tin, wrap it twice in glad wrap (plastic wrap) and put it in the freezer.

      Hope that helps!!

      xx

  26. Nat December 18, 2013 at 1:02 pm #

    Hi Bronnie,

    I have made IMBC following your method and it was amazing! I’m going to make it again for xmas cupcakes, but was wondering, at what stage do I add gel colouring to make the buttercream green?

    Thanks!

    • BronnieBakes Admin December 19, 2013 at 1:17 pm #

      Hi Nat :-)

      Great to hear you love the IMBC!!! I add my colouring once I have finished mixing in the butter

      xx

  27. Wirda February 3, 2014 at 6:19 pm #

    Hi Bronnie,
    Just wanted to know if IMB store well in the fridge? Need to make in advance then take it to location to assemble the cake. Its a fair drive to the location like 2hrs. Or do you think its best to make the IMB on the day of the event?
    By the way, love your tutorials.
    cheers

    • BronnieBakes Admin February 3, 2014 at 7:01 pm #

      Hi Wirda :-)

      IMBC can be kept at room temperature for 3 days in an air tight container (although if it is 40 degrees I wouldn’t do this) and up to 3 weeks in the fridge. If you keep it in the fridge it will harden and you will have to rewhip it and personally I don’t think it tastes anywhere as nice as freshly made IMBC. I like to make mine the day of the event or the day before (and I leave it on the bench). Because the egg whites are cooked with the sugar syrup it is fine to be left at room temperature. If it is a stinking hot day I would leave it in front of air conditioning (cakes with fondant) and cupcakes in the fridge.

      Hope that helps!
      x

      • Wirda February 4, 2014 at 11:27 pm #

        Thanks Bronnie for the tips, fingers cross that it won’t be that hot for the wedding. I might try to make it the night before, the cake should be pretty easy assemble.
        thanks again.

        • Wirda February 21, 2014 at 9:34 am #

          OH my goodness, this filling is delicious and so easy to make. Big hit at the cake testing weekend for the bride and room. Thanks, this will be my favourite filling to use from now on. ;-))))))

          • BronnieBakes Admin February 22, 2014 at 12:36 pm #

            I’m so happy to hear that Wirda!!

  28. Zoe April 27, 2014 at 8:50 pm #

    I’ve never made anything like this before and it was wonderful, thanks for the tutorial made things so easy. tasted great

  29. Maria Eugenia Carpio May 24, 2014 at 1:07 pm #

    Hi Bronnie!!! I am not sure how much sugar to use, because it was not so clear in my computer sound. I think I heard 295 grms of sugar. I am happy to know that I have to wip more the butter and egg whites to reach the desired consistency and be able to decorate the cake with flower that will keep the shape. If the mixture does not reach the right consistency can I add more powedered sugar??? Thank you very much for your kind attention. From Caracas, Venezuela

    • BronnieBakes Admin May 24, 2014 at 2:38 pm #

      HI Maria :-)

      It is 285g of sugar which is boiled with the water and an extra 55g sugar which you add to the egg whites once they are at soft peaks. You need 455g of butter but I wouldn’t add extra sugar. I have made this so many times and occasionally during hot weather I need to put my mixture in the fridge to harden up a little but otherwise the quantities listed are fine.

      All the best!

  30. Paulette September 6, 2014 at 7:02 am #

    Hi – I see you mention in your other recipe for IMBC that you use 285grms of castor sugar – in this you just say sugar – so is it normal sugar I use or Castor?..also salted or unsalted butter? Thanks heaps :-)

  31. Paulette September 7, 2014 at 6:04 pm #

    Don’t worry – I used unsalted butter and castor sugar and it was a success!…thank you for a great tutorial!!…First time ever making this and it worked perfectly – thanks to you! :-)

    • BronnieBakes Admin September 8, 2014 at 11:01 am #

      oh yay – glad it worked!!! Yes – I use castor sugar and unsalted butter. Sorry for my late response!!!!

      x

  32. Cheryl September 23, 2014 at 6:52 am #

    Hi there, Can I fill the cake with the Imbc and ganache it, then fondant it and leave it out overnight without the Imbc breaking down or does the cake need to be refrigerated until the day the cake is needed then fondant it. Any help appreciated

    • BronnieBakes Admin September 23, 2014 at 7:22 am #

      Yes – absolutely! leave it at room temperature if you have covered it in fondant. IMBC can stay at room temp for 3 days and in the fridge for 7, but if you put fondant in the fridge it will sweat and ruin.

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