Italian Meringue Buttercream is a silky smooth frosting using egg whites and hot sugar syrup for a light and stable frosting, perfect for decorating cakes and cupcakes.
Italian Meringue Buttercream Frosting is a wonderful frosting to have in your frosting arsenal.
While it's similar to Swiss Meringue Buttercream in both taste and texture, this Italian meringue version uses hot sugar syrup slowly poured into whipped egg whites to create a silky smooth frosting, which is buttery rich with a light touch of sweetness.
It's not nearly as sweet as a traditional American buttercream frosting, which is mainly confectioners sugar and butter. The egg whites make it much lighter and there is absolutely no grainy texture, which is common with American Buttercream.
Why this frosting is so great:
- Sweet, but not cloyingly sweet
- Light and silky smooth
- More stable than traditional American Buttercream
Ingredients and Tools
Ingredients
Standing Mixer
While you could make this without a standing mixer, I highly recommend having one for this recipe so you don't burn yourself when pouring the hot sugar syrup. Plus, the egg whites mix for a very long time as does mixing in the butter. Using a hand held mixer will be quite tedious and the standing mixer makes the whole process way easier.
candy Thermometer
As with the standing mixer, this recipe will be much easier with a candy thermometer than without. Unlike Swiss Meringue buttercream which in a pinch can be make using boxed pasteurized egg whites or just by testing once the sugar has dissolved, this recipe really does rely on the thermometer to ensure the sugar syrup is the right temperature. If it's too hot or too cool it will either harden or not fully incorporate when you add it to the egg whites.
If you don't have one, you're cooking the sugary syrup to the soft ball stage of candy making. To test this without a candy thermometer, fill a glass or bowl with cold water. When the sugar syrup starts to boiling, you can test it by dropping a bit into the cold water.
When you remove it the sugar syrup should form a soft, pliable ball. It it hardens that means the sugar syrup it too hot.
How to make
Step 1: whip egg whites
Using the whisk attachment in the bowl of a large standing mixer, mix the egg whites and cream of tartar on medium speed until frothy. Slowly add ¼ cup of sugar and turn up the speed to medium and beat until soft peaks form.
While the eggs are beating, start heating the sugar syrup. You want them both done about the same time.
If the egg whites reach still peaks prior to the sugar syrup reaching the right temperature, turn the speed to the lowest setting and mix until the syrup is done.
Step 2: heat sugar syrup
Add the remaining sugar and water to a medium saucepan and mix until combined. Cook a few minutes over low heat until the sugar is dissolved the sugar syrup looks clear.
Once the sugar dissolved, turn the heat up to medium and heat the sugar syrup without stirring until it reaches 235-240 ℉.
Once it hits the right temperature immediately remove from heat.
Step 3: add sugar syrup
While mixing the egg whites on low, very slowly and carefully pour the hot sugar syrup down the sides of the bowl.
Once you've added all the sugar syrup to the egg whites, turn up the speed to medium to medium high and continue whipping the egg whites until they cool down completely and no longer warm to the touch, about 5-10 minutes.
Step 4: add butter
Once the egg whites have cooled, you can optionally switch the attachment from a whisk to a paddle attachment. This can help keep the frosting from breaking/getting watery but it is not required.
Mixing on low, slowly start adding the softened butter one tablespoon a time, letting each piece combine before adding the next.
If the frosting starts to get liquidy or soupy, put in the fridge for 15 minutes to firm up, then continue mixing/adding the butter. See troubleshooting section for more information.
Once all the butter is combined, turn up the speed and continue mixing. Once the buttercream comes together add the vanilla and mix until combined. Then the frosting is ready to use on your favorite cakes, cupcakes, and filling macarons and other desserts!
Tips
- Make sure there are no egg yolks or any oil in the bowl or utensils used to mix the egg whites. This can cause the egg whites to not whip up properly.
- If you want a sweeter frosting, you can add up to ¼ cup more sugar.
- You can add up up to another stick of butter. I personally prefer only two stick of butter, I think its more marshmallow like and light but adding more will give it a thicker texture and more buttery flavor.
- Switching to a paddle attachment before adding the butter can help keep it from curdling/turning soupy. It’s not necessary though, if it does turn liquid you can always put in the fridge to firm up.
Troubleshooting Q&A
Why are my egg whites not whipping up?
Make sure there is no trace of egg yolks or oil in the bowl or on any utensils.. Any oil can cause the egg whites not to whip up properly. Also boxed egg whites also might not whip like fresh egg whites.
Why is my frosting a soupy curdled mess?
If the egg whites haven't cooled enough before adding the butter, the frosting mixture can sometimes break and separate. It will look grainy, curdled or really soft and soup like.
If this happens, don't worry! It's super common, especially if you don't switch to a beater attachment and continue to mix with a whisk attachment.
Just pop the whole bowl in the fridge for about 15-20 minutes to firm up. Then, continue mixing and adding the butter. It will eventually come together to a silky smooth consistency.
Can I add food coloring?
Yes, this is a great frosting to color with food coloring. I highly recommend using gel food coloring for more vibrant colors that won't throw off the texture with extra liquid you get in water food colors.
Just add the food coloring in at the end and mix until combined.
How long does this frosting last and can it sit out?
This frosting will last up to a week in the fridge in an airtight container.
Provided there is nothing else in the cakes or cupcakes that needs to be refrigerated, frosted cakes and cupcakes can sit out up to a day if it's not too warm out.
Storing and Making Ahead
This is great frosting for wedding cakes and other special occasion cakes because it very stable against the heat, much more so than American Buttercream.
The frosting can sit at room temperature for up to a day and can be stored in the fridge in an airtight container for up to a week.
The frosting can be frozen for up to two months. When ready to use, let defrost in the fridge and then come to room temperature. Rewhip before using.
FROSTING CAKES AND CUPCAKES
This Italian Meringue Buttercream recipe makes about 2 ½ cups frosting. This is enough to cover about 18-24 cupcakes (depending on how much frosting you use) or a 9×13 inch cake.
This frosting is very light and smooth, and as you can see it the pictures, it pipes beautifully.
LOOKING FOR MORE UNIQUE FROSTING RECIPES? CHECK THESE OUT!
- Mint Chocolate Chip Frosting
- Peanut Butter Frosting
- Cookie Dough Frosting
- Coffee Buttercream Frosting
- Almond Buttercream
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Italian Meringue Buttercream Frosting
Equipment
- Standing Mixer
INGREDIENTS
- 4 egg whites 4 oz
- 1/4 tsp cream of tartar
- 1 cup cup sugar divided
- 1 cup unsalted butter, softened cut into 1 tbsp pieces, see notes for using salted
- ¼ cup water
- ¼ tsp salt
- 1 tsp vanilla
Instructions
- In the bowl of a standing mixer with a whisk attachment, add eggs, and cream of tartar. Mix on medium until frothy and then slowly add ¼ cup of sugar.
- Turn to medium high and mix until soft peaks form.
- While whipping the egg whites, start heating the sugar syrup. You want them both done about the same time, so if the egg whites reach soft peaks prior to the sugar syrup reaching the right temperature, turn the speed to the lowest setting and continue mix until the syrup is done.
- To make the sugar syrup, add the remaining 3/4 cup of sugar and water to a medium saucepan. Stir to combine.
- Cook a few minutes over low heat until the sugar is dissolved the sugar syrup looks clear.
- Once the sugar dissolved, turn the heat up to medium high and heat the sugar syrup without stirring until it reaches 235-240 ℉.
- Once it hits the right temperature immediately remove from heat.
- While mixing the egg whites on low, very slowly and carefully pour in the hot sugar syrup.
- Once you’ve added all the sugar syrup to the egg whites, turn up the speed to medium to medium high and continue whipping the egg whites until they cool down completely and no longer warm to the touch, about 10-15 minutes.
- Once the egg whites have cooled, starting adding the softened butter one tablespoon a time, making sure each piece is combined before adding the next.
- Also, switching to the paddle attachment at this time can help keep the buttercream from breaking or curdling, but is not necessary.
- Continue mixing until the buttercream comes together to a silky smooth frosting. If the frosting starts to turn liquid or soupy, put in the fridge for 15 minutes to firm up, then continue mixing. See troubleshooting for more info.
- Once the buttercream comes together to form a smooth frosting, add the vanilla and salt and mix until combined. Then the frosting is ready to use on your favorite cakes and desserts.
Notes
- If using salted butter, omit extra salt or decrease to just a pinch.
- Make sure there are no egg yolks or any oil in the bowl or utensils used to mix the egg whites. This can cause the egg whites to not whip up properly.
- If you want a sweeter frosting, you can add up to ¼ cup more sugar.
- You can add up up to another stick of butter. I personally prefer only two stick of butter, I think its more marshmallow like and light but adding more will give it a thicker, more buttery flavor and texture.
- Switching to a paddle attachment before adding the butter can help keep it from curdling/turning soupy. It's not necessary though, if it does turn liquid you can always put in the fridge to firm up.
Angie says
Will this work for cake filling between layers?
Sophia says
Yes, it’s great for layer cakes.