Learn how to make the silkiest Swiss meringue buttercream that’s easy to work with and not too sweet! Complete with troubleshooting tips and tricks.
Are you looking for a lighter and more delicious alternative to the traditional American buttercream? Or want to expand your baking/cake-making repertoire? If so, Swiss meringue buttercream is precisely what you want to be looking into. And I’ll be sharing all of my tips and tricks for this beautiful buttercream, as well as some variations that you can try out!
What is Swiss Meringue Buttercream?
Swiss meringue buttercream (abbreviated SMB for the rest of this, thanks!) is a meringue-based frosting that is common atop cupcakes, cakes, and wherever else you would see frosting. Meringue-based means that most of its mass is composed of whipped egg whites. This makes it much lighter than your traditional American buttercream, which is primarily creamed butter and sugar.
What is the difference between Swiss Meringue Buttercream and American Buttercream?
Swiss meringue buttercream is meringue-based, less sweet, and silkier in texture. American buttercream is simpler, more structurally sound, denser, and much sweeter.
American buttercream is really straightforward and versatile. It’s made of butter and sugar, with optional flavorings. It’s easy to whip up and works great as a stiffer frosting. For example, I use American buttercream to make buttercream roses and flowers!
However, I don’t know many people who joyously consume all layers of normal buttercream. It helps to provide moisture and additional sweetness, but is more of a means to an end instead of a star element.
Why I started making Swiss meringue buttercream
I’m not exaggerating when I say that I almost gave up on cakes and cupcakes when I thought that American buttercream was the only type of frosting to use. Most of my memories of frosting are of cloyingly sweet cupcakes from bakeries, birthday parties, and my own amateur endeavors. Coming from an Asian household, the sweetness of American buttercream really didn’t cut it.
When I started cake decorating, I wanted something that would be structurally similar to American buttercream. But I really couldn’t justify making batches and batches of butter x sugar, for the sake of myself and the people I was feeding these cakes to. The search led me to SMB <3
You’ll notice that most of my cake recipes use SMB, and none of them use American buttercream. However, they’re really interchangeable so make what you prefer!
Other Types of Buttercream – Italian, French
Italian buttercream is also meringue-based. The technique is a little more involved than for Swiss meringue buttercream. The method involves heating sugar and drizzling it in at a specific temperature (necessitating a candy thermometer). It also loses its consistency quickly.
French buttercream is custard-based, meaning that it uses egg yolks. It’s quite similar to pastry cream and has sharp definition which makes it useful for piping. The color is also unique – because it’s made of egg yolks, it strays from the standard whiteness of other frostings.
How Swiss Meringue Buttercream Works
Frosting is frosting is frosting, but there are some things you should know about SMB! Namely, how it is used and how absolutely delicious it is.
What does Swiss meringue buttercream taste like?
A DREAM! Silky, creamy, decadent, buttery, and so so smooth. SMB is flexible in that you can add as much, or as little, sugar as you want and it hardly changes the texture. Although it gets its light and airy texture from all of the whipped egg whites, it tastes like a normal, buttery, and sugary frosting.
How does Swiss meringue buttercream pipe?
SMB works great for cupcake frosting, crumb coating/cake frosting, as well as basic cake decorating techniques. My favorites are a rope border and a classic star swirl!
Be careful when trying to construct more delicate decorations such as roses. I prefer to use American buttercream because its much stiffer, but I also don’t end up eating the buttercream roses…
How do you store Swiss meringue buttercream?
The beautiful thing about SMB is that it doesn’t turn crusty like American buttercream after sitting at room temperature. It maintains its elegant and glossy sheen. It’s also easy to make ahead and store!
If you’re looking to store it for longer than 1-2 days, you can refrigerate or freeze it. After you finish making SMB, store it in an airtight container and wrap it tightly.
How to refrigerate Swiss meringue buttercream
SMB can be refrigerated for up to 5 days. To use, take it out and let it sit at room temperature for at least 30 minutes to soften. Then, re-whip with a hand or stand mixer fitted with a paddle attachment until it returns to its original texture.
How to freeze Swiss meringue buttercream
You can make SMB ahead of time and freeze until you need to use it. Be sure to place in a (preferably) plastic container with lid or plastic bag. Swiss meringue buttercream can be stored in the freezer for up to 3 months.
To use, let thaw until it reaches room temperature. Then, re-whip with a hand or stand mixer fitted with a paddle attachment until it returns to its original texture.
Swiss Meringue Buttercream Ingredients
The basic SMB recipe only needs 5 ingredients that are all readily available!
Whipped egg whites is what gives this frosting volume. They are gently cooked to a safe temperature so you don’t need to worry about raw eggs.
It is essential to separate the egg whites completely from the yolk. If there is any fat from the egg yolks or otherwise, you will not be able to reach stiff peaks.
I like to use the shell to help separate the whites, but there are many other ways to complete this step!
Unlike traditional buttercream which uses very fine confectioners’ sugar, SMB uses common granulated sugar. The sugar will be heated with the egg whites and will eventually dissolve.
The sugar content also does not have a large effect on the structure of the buttercream so this is a great way to decrease sugar. I use ¾ cup in this recipe but I more commonly use around ½ cup. I believe that normal recipes use closer to 1 cup, so it is all up to your personal preference!
Butter is what makes meringue (whipped egg whites) into meringue buttercream! Make sure that your butter is at room temperature (around 65°F). Room temperature butter is cool to the touch but still firm. On average, you can take your butter out of the fridge right when you begin and it should be around the right temperature when you need it.
Usually, problems with SMB come from the temperature of the butter or the whipped egg whites. I will go into more detail below!
Vanilla Extract and Salt
Vanilla extract is used for the classic vanilla frosting flavor. You can add in or try out other extracts like coconut, almond, lemon, to name a few.
The pinch of salt is meant to balance out the sugar and provide a more complex flavor. Don’t worry, you won’t be able to taste it in the frosting!
This recipe is a great foundation to build upon! One of my favorite things is to play with cake and frosting flavor pairings. Here are a few ideas to get you started:
- White Chocolate Swiss meringue buttercream (paired with a coconut cupcake!)
- Chocolate Swiss meringue buttercream (using melted and cooled chocolate)
- Oreo Swiss meringue buttercream
- Earl Grey Swiss meringue buttercream
Making Swiss Meringue Buttercream
Enough logistics, let’s get into it! (oh wait one more, make sure you bring your butter to room temperature)
Heating egg whites and sugar
In a dry, grease-free, heatproof mixing bowl (or in the bowl of a stand mixer), whisk together egg whites and sugar. Set bowl over a double boiler (saucepan filled with a few inches of simmering water) over medium heat. Make sure that the bowl does not touch the water.
- A homemade double boiler is made of two components: a small saucepan or pot and a heatproof bowl. In the pot, bring an inch or so of water to a simmer and place the bowl on top, making sure that the bowl does not touch the water. This creates a slow and low heat to gently cook whatever is in the bowl!
Whisk the whites and sugar constantly until sugar is dissolved and mixture has thinned out, or until mixture reaches 160°F, about 4 minutes. A candy thermometer is useful here, but you could also just use your fingers to test if the sugar has completely dissolved. That is usually a good indication that the egg whites are ready.
Transfer to stand mixer
When the mixture is still warm, transfer to the bowl of stand mixer fitted with a whisk attachment. On high speed, beat the mixture until stiff glossy peaks form and the meringue is no longer warm to the touch, at least 10-15 minutes. If it still feels warm, wait until room temperature before adding butter.
Stiff peaks are when you lift the whisk attachment and the egg whites hold its shape in a peak. If the peaks fall over, those are medium or soft peaks and you should keep on beating.
I would not recommend using a handheld mixer because it will take significantly longer.
Adding in Butter
On medium-high speed, add the butter 1 tablespoon at a time. Wait for the butter to fully mix in before adding the next tablespoon. The mixture may look curdled, but just keep adding butter and it will come together!
Some recipes call for using a paddle attachment, but I find that I need the whisk attachment to generate more volume. It should work fine if the butter is at room temperature!
After all the butter has been added, turn the mixer down to medium speed and beat until thick and creamy, around 2-4 minutes more. Finally, fully beat in the vanilla and pinch of salt, about 30 seconds.
Troubleshooting Swiss Meringue Buttercream
SMB is nothing short of amazing, but high reward also comes with high(er) risk. My personal journey consists of many regrettable batches that I threw away but now realize that I could have rescued :'(
My most common problem was having curdled looking buttercream. It was quite discouraging and I really did try every proposed solution I found. Part of the problem was that I didn’t know where the problem was!
I placed it over a double boiler – it turned into a soupy mess. Then, I tried putting it in the fridge overnight – it didn’t change at all. I started from scratch again and again because I thought I didn’t whip my egg whites enough, or maybe I added the butter too fast and it couldn’t be absorbed, or maybe I somehow got oil in my mixing bowl.
The problem was that my butter was not warm enough. The curds I saw in my buttercream were actually little chunks of butter that couldn’t be creamed into the egg whites. My kitchen is a little colder than average so it’s difficult for my butter to get to room temperature naturally.
The solution? Well, I’ll talk about that below. But it came from scouring the Internet and took me into the recesses of Youtube video comments. So instead of you having to do that, I’m letting you into my little SMB secret.
The moral of the story is – don’t give up until you’ve tried everything! And once you get it right, you’ll be coming back to this recipe again and again.
Swiss meringue buttercream looks curdled/chunky
This isn’t the most common or the earliest mistake you may run into, but it was the most profound error I came across. This is because of two possible reasons. One, you just need to keep beating the frosting and it’ll come together soon enough. Two, your butter was too cold to begin with. Here’s the solution for the second problem:
Use a Hairdryer to Fix Curdled Buttercream
Enlist the help of a hairdryer!! While your stand mixer is beating on medium-high speed, blow-dry the bottom of the mixing bowl using medium-high heat. This allows the butter to slowly melt into the egg whites and cream together.
This is different from a double boiler because the heat is less intense and your frosting is constantly moving in the mixing bowl. Therefore, the heat distributes more evenly and avoid melting the buttercream altogether.
This can take up to 10 additional minutes but you will slowly see the buttercream coming together.
Egg whites won’t form stiff peaks
If there is any bit of fat or oil in your mixing bowl, the egg whites will not whip up. This includes any residual oil or fat from egg yolks.
When you wash your mixing bowl, be sure to use dishwashing liquid to get rid of all grease. To go an extra step, wipe down the bowl with an acid such as lemon juice or vinegar.
If you accidentally get egg yolk into the mixture, remove eggs from the mixing bowl and clean the bowl thoroughly. You can also crack the eggs into a separate bowl first to ensure that there is no accidental mix-up!
Swiss meringue buttercream looks melted
If there is no curdling and the frosting just looks liquid, pop it in the fridge or freezer. Check it after 10 minutes and re-whip. If it still doesn’t come together and become creamy, repeat the chilling procedure. Don’t leave it in the fridge for too long or else it will solidify.
Try out Swiss Meringue Buttercream!
I hope this was helpful and that you will end up loving SMB as much as I do. Let me know how it goes – always happy to chat!
Recipes that use Swiss meringue buttercream
Here are a few Alice’s Cookbook favorites that highlight different types of SMB!
- Coconut white chocolate cupcakes
- Black sesame layer cake
- Earl Grey cupcakes with salted caramel
- Coffee oreo cupcakes
The Best Swiss Meringue Buttercream
- 3 large egg whites, room temperature 120 grams
- ¾ cup granulated sugar less if desired
- ¾ cup unsalted butter, room temperature 1½ sticks
- 1 tsp vanilla extract
- pinch of salt
- In a dry, grease-free, heatproof mixing bowl (or in the bowl of a stand mixer), whisk together egg whites and sugar. Set bowl over a double boiler (saucepan filled with a few inches of simmering water) over medium heat. Make sure that the bowl does not touch the water. Whisk the whites and sugar constantly until sugar is dissolved and mixture has thinned out, or until mixture reaches 160°F, about 4 minutes.
- When the mixture is still warm, transfer to the bowl of stand mixer fitted with a whisk attachment. On high speed, beat the mixture until stiff glossy peaks form and the meringue is no longer warm to the touch, at least 10-15 minutes. If it still feels warm, wait until room temperature before adding butter.
- On medium-high speed, add the butter 1 tablespoon at a time. Wait for the butter to fully mix in before adding the next tablespoon. After all the butter has been added, turn the mixer down to medium speed and beat until thick and creamy, around 2-4 minutes more. Finally, fully beat in the vanilla and pinch of salt, about 30 seconds.