Learn how to make Swiss Meringue Buttercream from scratch. This silky smooth frosting has a soft, velvety texture, making it perfect for frosting layer cakes and cupcakes. You will need a candy thermometer for this recipe.
Look at her in all her silky glory 😍
This easy Swiss Meringue Buttercream recipe is a game-changer. Think smooth, light and creamy frosting that’s stable, delicious and pipes extremely well. It’s made using just four ingredients and has an enviable melt-in-your-mouth texture.
While Swiss Meringue Buttercream is more involved than regular American-style buttercream, it does have some very attractive qualities that make it well worth the effort. From its unique, velvety texture to its crust-free exterior, Swiss Meringue Buttercream is perfect for frosting layer cakes and decorating cupcakes.
why you will love this frosting
- It has an incredibly silky texture
- It pipes beautifully
- You only need four ingredients
- It tastes INCREDIBLE!
Swiss Meringue Buttercream is a frosting made from cooked eggs, caster sugar and butter. It’s smooth and creamy, light and airy. When recipe testing, I found that too much butter could leave you with an overwhelming buttery taste and a greasy texture. And too much sugar made it far too sweet. My recipe calls for just enough butter and sugar to make a rich and creamy frosting that’s stable, smooth and just sweet enough.
The benefits of smbc
Are you wondering if Swiss Meringue Buttercream (SMBC) is right for you? Here’s a snapshot of how it compares to regular buttercream.
- It’s not as sweet (but it’s still sweet). While a similar quantity of American-style buttercream could have anything from 5-7 cups of icing sugar or powdered sugar, this recipe only has one and a quarter cups of caster sugar. SMBC is often touted for being less sweet than traditional frosting recipes. But keep in mind, it is still frosting and it is still sweet.
- It has a lighter texture. Traditional buttercream can have a thicker, denser texture and it will develop a crust over time. On the other hand, SMBC is light and airy, and just about melts-in-your-mouth. It has a texture that’s similar to whipped cream. It also does not form a crust, making it ideal for creating smooth layer cakes.
- It’s easy to work with. While it’s a little bit more fiddly to make, SMBC works wonderfully well when frosting layer cakes and it also pipes beautifully. It’s smooth and soft and doesn’t clump or go grainy.
- Egg whites: We use six egg whites in this recipe. It doesn’t matter if they’re fridge cold or room temperature, but make sure there’s not a speck of egg yolk in them.
- Caster sugar: While regular buttercream recipes are typically made using icing sugar or powdered sugar, this recipe calls for caster sugar or granulated sugar. You’ll heat the egg whites and caster sugar together on the stove so the sugar will dissolve and your frosting won’t be grainy.
- Unsalted butter: Butter is one of the key ingredients in this recipe. Without it, you have a marshmallow frosting recipe. With it, you have a softly sweet buttercream. I recommend using unsalted butter and adding a pinch of salt to taste, otherwise the frosting will be too salty. Your butter will need to be cubed and cold (but not too cold). More on that below.
- Vanilla extract: To flavour this Swiss Meringue Buttercream, we use a few teaspoons of vanilla extract.
how to make swiss meringue buttercream
There are three key steps to making perfect Swiss Meringue Buttercream. The first is heating the egg whites and sugar over a double boiler, the second is whipping the egg whites to form stiff peaks, and the third is adding the butter and flavourings.
Let’s break it down step-by-step to ensure you can make perfect SMBC every single time.
Make a double boiler: Before you begin, choose a medium saucepan and a medium heatproof bowl that you can use for your double boiler. You’ll want to pick a bowl that will neatly fit on top of your saucepan, but the bottom of your bowl CANNOT be touching the water below. (See above photo).
Clean your bowl: Wipe down your bowl, making sure there’s no grease, residue or crumbs left in it. And then make sure it’s completely dry.
Prepare your butter: Remove your butter from the fridge and cut it into 1/2 inch cubes. Keep it in the fridge until you are ready to make your frosting. When you are about to start, take it out of the fridge and set it aside on the bench. You need your butter to still be cool, but not fridge cold.
2. heat egg whites and sugar
Separate egg whites: Carefully separate your eggs, ensuring no egg yolks leak into your egg whites. If there’s even a speck of egg yolk, it can cause problems later when you attempt to beat your egg whites to stiff peaks.
Heat egg whites and sugar: Add egg whites and sugar into your mixing bowl and whisk by hand just to combine. Place your bowl on top of your saucepan that’s filled with a few inches of water and turn on to medium heat. Continue to whisk egg mixture by hand while they slowly heat from the steam below.
The egg mixture will turn thick and frothy over time, and the sugar will dissolve completely. You’ll know it’s ready when your mixture has reached 70 C / 160 F, which you can check using a candy thermometer. They’re inexpensive and easy to use. Remove from heat.
2. whip to stiff peaks
Place egg mixture in the bowl of a stand mixer fitted with a whisk attachment. Whisk on medium speed until your egg whites reach stiff peaks. They should be thick, glossy and cloud-like. This can take around 10 minutes or even longer.
At this stage, your egg whites should hold their shape and not droop. The mixture should also be completely cooled.
3. Add butter
Turn your mixer down to low speed, then slowly start adding your butter, piece by piece. As you add your butter, your mixture may turn soupy, and even eventually look curdled – this is ok.
Continue until you’ve added all your butter. Turn your mixer up to medium speed and continue to whisk. It’s common for your frosting to go through a stage where it looks curdled. But just keep mixing and eventually it’ll come together. (And if it doesn’t, the fridge is your friend. More on that below).
Finally, add vanilla and salt. Mix briefly. Then remove your bowl from the mixer and use a spatula to give it one final stir by hand, getting rid of any air bubbles.
Frosting should be thick and smooth and taste AMAZING.
It does take a long time (10 minutes or more) to reach stiff peaks using a powerful stand mixer, so keep going if you are just feeling impatient. However, if your eggs are just not whipping to stiff peaks, it may be that there was some egg yolk that slipped into your mixture or your bowl had some grease or residue in it. In this case, I encourage you to stop here and try again.
Once you add your butter, your stiff peaks will disappear and your mixture may appear thin and runny. This is ok. It may mean that your eggs were still slightly warm and/or your butter was too warm. Try whisking for a few more minutes and you may find your mixture will eventually come back together on its own. If it doesn’t, place your bowl in the fridge for 20 minutes to let the mixture firm up slightly and whisk again.
Don’t panic – this is ok. It is often the result of your mixture still being a bit warm and your butter being too cold. Keep calm and keep whisking, your frosting will eventually come together.
Swiss Meringue Buttercream is whiter than regular buttercream, but it is not white. The large amounts of butter in it will turn it off-white or cream coloured. The type of butter you use (and its subsequent colour) will tint the final result.
top tips for perfect Swiss meringue buttercream
- Ensure your mixing bowl is completely clean.
- Be careful when separating the egg whites.
- Make sure your sugar is completely dissolved.
- Don’t stop whisking until your egg whites reach stiff peaks.
- Make sure your mixture is completely cooled before adding your butter.
- Ensure your butter isn’t too warm – and add it slowly.
- Keep calm and keep on whisking.
frequently asked questions
Yes. You can make this frosting ahead of time and keep it in the fridge. The butter will solidify making it firm. To use, let it come back to room temperature, then whisk it again until smooth and creamy. Personally, though, I do find this frosting is at its silkiest when it’s freshly made.
Yes. See above. You’ll need to let it thaw and come back to room temperature before re-whipping.
This recipe makes around four cups of frosting. It’s enough to frost a two-layer 8-inch cake, a three-layer 6-inch cake or generously pipe 12 cupcakes.
Yes. Keep in mind, that if you double the recipe, it may take longer to make. For example, it’ll take longer to whip 12 egg whites to stiff peaks.
more frosting recipes
An easy recipe for homemade Swiss Meringue Buttercream.
- 290 grams (1 and 1/4 cups or 2.5 sticks) unsalted butter, cut in 1/2 inch cubes
- 6 egg whites
- 250 grams (1 and 1/4 cups) caster sugar or granulated sugar
- 2 teaspoons vanilla extract
- Pinch of salt
- Before you begin: Chose a medium saucepan and a medium heatproof bowl that you can use for your double boiler. You’ll want to use a bowl that will neatly fit on top of your saucepan, but the bottom of the bowl CANNOT be touching the water below. (See photo below). Wipe down your bowl, making sure it’s completely dry and there’s no grease, residue, or crumbs left in it. Remove butter from the fridge and set aside. Carefully separate your egg whites.
- Add egg whites and sugar in your mixing bowl and whisk by hand to combine. Place bowl on top of a saucepan that’s filled with a few inches of water and turn on medium heat.
- Continue to whisk by hand until your sugar has completely dissolved and your egg mixture has reached 70 C / 160 F. You can check this using a candy thermometer. The eggs will be thick and frothy. Remove from heat.
- Place eggs in the bowl of a stand mixer fitted with a whisk attachment. Whisk on medium speed until egg whites become thick and voluminous and reach stiff peaks. This can take around 10 minutes. The egg whites should hold their shape and not droop. The mixture should also be completely cooled.
- Turn your mixer down to low speed, then slowly add your butter, piece by piece. As you add your butter, your meringue mixture may turn soupy, and/or eventually look curdled – this is ok.
- Continue until you’ve added all your butter. Turn your mixer up to medium speed and continue to whisk until frosting comes together and is smooth again. Do not worry about over-mixing – keep going.
- Finally, add vanilla and salt. Mix briefly. Then remove bowl from mixer and use a spatula to give it one final stir by hand, getting rid of any air bubbles.
Butter: Your butter needs to be cool, but not fridge cold. I recommend getting it out of the fridge when you are ready to start, so it has time to cool slightly.
Soupy frosting: If your meringue wasn’t completely cooled or your butter was too warm, your meringue may appear thin and soupy after you add the butter. Don’t worry if this happens, you can pop it in the fridge, wait 20 minutes and then whisk again.
Curdled frosting: Once you add the butter, your frosting may appear curdled. This is normal. Keep whisking and it will come back together and be smooth and creamy again. For more troubleshooting tips, check out this article by Serious Eats.
Make ahead: You can make this frosting ahead of time and keep it in the fridge. The butter will solidify making it firm. To use, let it come back to room temperature, then whisk it again until smooth and creamy. You can also freeze it. In the same way, you’ll need to let it thaw before whisking again.