Italian Meringue Buttercream (IMBC)
Italian Meringue Buttercream (IMBC) is my favorite cake frosting. This is the exact recipe I used for 10 years in my wedding cake business.
Table of contents
Why this is my favorite buttercream
Italian Meringue buttercream has the perfect balance of rich flavor from the butter, and lightness from the meringue. It’s not overly sweet and it can be flavored with an endless variety of add-ins. It’s strong enough to pipe buttercream roses and stays soft at room temperature so it melts in your mouth.
Ingredients
- Water – To make the sugar syrup.
- Granulated sugar – Added in two stages. Dry sugar starts the meringue, then sugar syrup “cooks” the meringue.
- Egg whites- Fresh or in-shell pasteurized egg whites can be used. If you use frozen egg whites read the label to be sure they can be whipped for meringue.
- Salt – Just a touch to balance out the flavor.
- Unsalted butter – Softened butter is whipped into the meringue base. Unsalted butter allows you to control the amount of salt in the recipe.
- Vanilla extract – Use natural vanilla extract for the best flavor. You can also use vanilla bean if you don’t mind the little specks.
Process Photos
See the recipe card for detailed measurements and instructions.
- Combine some of the sugar with water in a small saucepan. Bring the syrup to a boil.
- While the syrup cooks, whip the egg whites with the remaining sugar.
- Bring the syrup to the softball stage (235°-240°F). Immediately remove from the heat.
- With the mixer running, add the syrup in a steady stream. Try to keep the stream of syrup between the whisk and the side of the bowl.
- Whisk until the whites are cooled to about 80°F.
- Add the room temperature butter a tablespoon at a time.
- Add the vanilla.
- The buttercream may look a bit curdled after adding the vanilla.
- Keep whipping until the buttercream is silky smooth and airy. Use immediately or keep at room temperature until ready to use (up to 1 day).
How to Store Italian Meringue Buttercream.
Because there is relatively low moisture in the buttercream, and high sugar content, Italian Meringue Buttercream can be held at cool room temperature for up to a day. After 1 day the buttercream should be refrigerated for 3-4 days or frozen for up to a month.
Proper syrup temperature is important for a silky smooth Italian Meringue Buttercream
This is a fairly standard Italian Meringue Buttercream recipe except for the temperature of the sugar syrup. A lot of recipes have you boil the syrup well into the firm ball stage (248°F), but I find this makes a buttercream with a texture that is too tight and marshmallow-y.
I like to boil the syrup to the softball stage (235°-240°F) for a slightly softer buttercream that whips to a little lighter.
How to fix Italian Meringue Buttercream
- If you’re working in a warm kitchen and your buttercream is a little too soft you can refrigerate it briefly and then re-whip it until it’s light and fluffy.
- If your buttercream is a little too cold you can warm the bowl and then whip it until it’s light and fluffy.
- To rewhip cold Italian Meringue Buttercream first bring it to room temperature. When you start whipping the IMB it may separate the look curdled.
- Use a blow torch or a bowl of warm water to warm the sides of the bowl as the buttercream whips.
- You’ll see the edges soften and and buttercream will come back together. Whip until the buttercream is silky smooth.
Pastry Chef tips for making perfect Italian Meringue Buttercream:
- If the meringue and/or the butter are too warm when they’re combined the buttercream will break down. If the buttercream becomes soupy and grainy the meringue has broken down and the buttercream can’t be fixed.
- If the butter is too cold when it’s added to the cooled meringue you’ll end up with lumps of butter that can’t be whipped out. Make sure the butter is soft and pliable, but not at all greasy or melted. The best temperature for the butter is about 70°F.
- Any extra buttercream can be double-wrapped in plastic (so it doesn’t pick up any off flavors) and frozen for a month. Bring it back to room temperature and then re-whip.
- The only limit to the flavors you can make with this buttercream is your imagination. You can add melted chocolate, lemon curd and/or lemon extract, orange zest, raspberry puree, instant coffee, whatever you can think of to create your favorite buttercream flavor.
Swiss Meringue Buttercream is very similar to IMBC except that you warm the sugar and eggs over a water bath rather than making a sugar syrup.
If you want a buttercream that is just as light and airy as a meringue buttercream, but with a slightly richer flavor and color, try making classic French Buttercream. It’s made with egg yolks instead of egg whites.
Now that you’ve made this recipe what should you do with the extra yolks? Check out this collection of recipes that use extra yolks for some great ideas.
If you love this recipe as much as I do, please consider leaving a 5-star review.
Italian Meringue Buttercream Recipe
Ingredients
- 2 ounces water (¼ cup)
- 8 ounces granulated sugar (1 cup, divided)
- 5 egg whites (room temperature)
- ¼ teaspoon table salt
- 1 pound unsalted butter (room temperature, cut into 16 pieces)
- 1 tablespoon vanilla extract
- Other flavorings to taste
Instructions
- Combine 2 ounces water with 3/4 cup (6oz) granulated sugar in a small saucepan. Cook the sugar syrup on medium high heat, stirring, until the sugar is melted. Once the syrup begins to boil do not stir the syrup. Allow it to cook to 235°-240°F (soft ball stage).
- While the syrup is boiling, whip 5 egg whites on medium high speed. When the whites are at soft peak reduce the mixer to medium low and slowly add the remaining 1/4 cup of sugar and ¼ teaspoon table salt. Increase the speed to medium high and whip to full peak.
- As soon as the syrup is at the correct temperature, remove the pan from the heat. With the mixer running on medium low, pour the hot syrup in a steady stream between the edge of the bowl and the whisk. Increase the speed to medium high and continue whisking until the whites are cooled to about 80°F.
- When the whites have cooled, with the mixer running on medium, add 1 pound unsalted butter one piece at a time. Add 1 tablespoon vanilla extract and increase the speed to medium high and whip until the buttercream comes together.
- Store at room temperature for up to 1 day then refrigerate or freeze.
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Equipment
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Eileen, I would like to make a cream cheese Italian meringue butter cream. Should I add cream cheese to the meringue after the butter, or should I make separate recipes for each and then combine them? Thanks for sharing your expertise. Judy
Hmmm, I’ve never tried this, but I’m intrigued by the idea. My first thought would be to replace some of the butter with cream cheese. Maybe half and half? That’s the ratio I use for my regular Cream Cheese Frosting. Also, a little squeeze of lemon juice will enhance the cream cheese flavor. If you try it, please let me know how it works. I might give it a try myself.
Hi,
what about adding cream of tartar to the egg whites?
I never do, but you certainly can if you’d like to.
I was excited to find such detailed clear information & instructions for this recipe, but really wanted to see the video that it lists above to watch; however, there is no link I could find anywhere on the page to view the video.
Am I missing something?
Hi Karen, I’m sorry for the confusion. I’m in the middle of making a change to how the videos display. Right now the recipe video is at the top of the post. If you’re working on a desktop the video should “follow” as you read. If you’re working on mobile, go to the top of the post and you should see the video. I apologize for any inconvenience.
Hi Eileen! I tried this recipe for my lemon cake using less butter and it came out so well. I added lemon zest and flavoring to the frosting and was so surprised at the compliments. I have a question though, can I add rum flavoring to IMBC? If so, does it matter what kind of rum? I have white rum but noticed that you used dark rum in your recipes. Also, can the rum be used in the cake batter as well? Is 2 TB the ideal amount to use for both frosting and batter and can the rum be used with lemon flavoring? Lastly, why can IMBC be left out at room temperature? I was thinking it should be refrigerated because of the egg content, yet my cake has sat out with no problems. Thank you for your patience in answering all of my qurstions!
Hi Kay, I’m glad your cake was a hit! I use plenty of rum in my cakes. Yes, you can certainly add a little to IMB, start with a tablespoon or two than adjust to your taste. I prefer the flavor of dark rum to light rum. Instead of baking it into the cake I like to put it in the syrup that I sprinkle on the cake. That way the flavor comes through. But you could add a tablespoon or so to the batter (vanilla is alcohol based). With lemon cake I like to use Limoncello. It’s wonderful on the cake and in the buttercream. IMB can be left at room temperature because the egg whites are “cooked” by the hot syrup. IMB is relatively high in sugar content and low in water content, which makes it an unfriendly environment for bacteria. I’ve left IMB at room temperature for a few days with no problem. I think more than a couple of days and the flavor might start to go off.
Off to buy dark rum and Limoncello! Thank you Eileen for your help and a wealth of information!
Sure. Have fun!!
Hi Eileen!
First attempt at IM Buttercream was a complete fail. Definitely added the butter too soon, which resulted in a runny buttery mess. Also used carton egg whites, which didn’t whip up nicely at all. Decided to give it another try about 2 weeks ago for a cake. Used fresh egg whites this time, whipped up great. Added the sugar/water mixture, everything was going perfectly. However…maybe like 10 minutes of whipping the meringue, it cooled, but the bottom of the stand mixer bowl was still fairly warm to the touch. Unsure if over-whipping would ruin the meringue, I added the butter and kept whipping. This time it wasn’t a complete pool of butter and sugar, but it for sure was still too loose. So, I kept the mixer going and rubbed ice on the bowl and it actually came together. I put it in the fridge… thinking, “I’ll just rewhip it in a half hour or so when I need it”…, but when I took it out, I ran my spatula through it and it had an odd texture. It looked like it was separating, and was watery. Scrapped it, and had to make American Buttercream.
Any tips? Can I do the rubbing of ice cubes on the side of the mixer technique to cool the bowl and meringue, before adding the butter? Or should I just let the mixture keep running until the bowl cools? Is 15-20 minutes too long??
I’m determined to master making IM Buttercream! Maybe a 3rd times the charm…
Hope to hear back!!
Hi Matthew – If you try to mix or whip the buttercream while it’s still cold from the refrigerator it will separate. You need to wait for it to come up to room temperature before you re-whip it. Even if it separates like that you can still save it. With the mixer running warm the bowl, either with a blow torch or a small bowl of hot water under the mixer bowl. It will take a few minutes, but it will come back together. I have even held the mixer bowl high above a low flame on my stove while whisking it by hand to warm it just a bit. Sounds like you did everything right and your buttercream would have worked. Next time just wait for it to soften up before you mix it. As far as the bottom of the bowl still being warm, I’ve found that just touching the bowl doesn’t always indicate exactly the temperature of the meringue. Try turning off the mixer and sticking your finger into the meringue. You might be surprised to find that it’s cooler than the bowl is. IM buttercream is much more forgiving than folks realize. I think many people end up scraping batches that can be saved. Good luck!