I will openly admit that American buttercream and I are not best friends. I want to like it. I’ve tried hard, but it’s just too sweet for my curmudgeonly nature.
Swiss meringue buttercream, on the other hand, is light, luxurious, easy to make, and perfectly pipe-able. It’s far less sweet than American buttercream and has an irresistible silky texture. I used it to frost this Chocolate Layer Cake—a crowd favorite in my family.
If you’re looking for a frosting to smooth over a cake or pipe into rosettes, a Swiss meringue buttercream is the answer to your cake decorating prayers.
This chocolate version of Swiss meringue buttercream is easy to make, is more stable than American buttercream, and stores well. You can completely frost a cake days in advance, keep it in the fridge, and bring it to room temperature just before serving for a beautiful result every time!
This frosting is for the chocolate-loving planners among us.
What Is Swiss Meringue Buttercream?
Swiss meringue buttercream has a base of egg whites and sugar heated to 160° F over a double boiler (a bowl set over a pot of simmering water). The combination is then whipped at high speed while adding butter a tablespoon at a time. Finally, fold in the chocolate. Easy peasy.
Heating the egg whites reduces the risk of any harmful bacteria from uncooked whites, while simultaneously dissolving the sugar. Couple that with the fat from butter, and you’ve got the telltale silky mouthfeel of Swiss meringue buttercream.
Is Swiss Meringue Buttercream Safe?
Yes, Swiss meringue buttercream is safe to eat. For this recipe, you’ll whisk the egg whites in a bowl set over simmering water until they reach 160°F. That will kill any risk of salmonella.
Ways to Adjust This Recipe
When writing this recipe, I used different amounts and different kinds of chocolate. I tried both semisweet and bittersweet chocolate. I also made batches with 8 ounces, 10 ounces, and 12 ounces of chocolate. In the end, I landed on 10 ounces of bittersweet chocolate.
For me, 10 ounces of bittersweet chocolate gave me the perfect balance of flavors and still provided that silky Swiss meringue buttercream texture. All of this to say: If you want to mix it up, feel free to play around with the chocolate ratios a little bit.
If you want an even richer buttercream, feel free to add up to an additional quarter cup of butter.
Troubleshooting Swiss Meringue Buttercream
Why is my buttercream grainy?
If your chocolate Swiss meringue buttercream is grainy, it’s probably one of two things. First, you didn’t dissolve the sugar well enough while whisking the eggs and sugar over the double boiler, or you cooled your chocolate a bit too much.
- To prevent grainy buttercream: Dip your index finger into the heated egg white and sugar mixture. Rub it between your finger and your thumb. If you feel any grittiness, keep whisking, and test again in a few minutes. It should feel completely smooth.
- Check the sides of the bowl: While whisking, it’s not uncommon for some small sugar granules to get stuck to the sides of the bowl. Use a spatula to incorporate it into the mixture.
- Over-cool chocolate: You might have cooled your chocolate too much, and when the cool chocolate is folded into the cool whipped egg white and sugar mixture you could get small flecks of chocolate.
Why is my Swiss buttercream too loose?
You just finished whipping in all that luscious butter and folding in the melted chocolate, only to have droopy frosting. Don’t panic! The egg whites were probably still a little warm when you started adding the butter.
- Pop the frosting into the refrigerator for about 20 minutes to let it cool down, then whip it again. It might look a little clumpy, but just keep going. You’ll probably need to re-whip it for about five minutes.
Can You Pipe Swiss Meringue Buttercream?
Absolutely!!! Pipe this homemade Swiss meringue buttercream into all the swoops and swirls your heart desires.
How Long Will Swiss Meringue Buttercream Last at Room Temperature?
My guess is you’re not planning to leave this cake on the counter for days on end. You probably just want to know if you can take the cake out of the fridge in the morning because you need room for all the other party food. The answer to that question is, “Yep, you sure can!” It can sit at room temperature all day.
Can I Make Swiss Meringue Buttercream Ahead of Time?
Yes, you can! Feel free to set yourself up for success by making this frosting up to four days ahead of time and keeping it covered in the refrigerator. You will need to re-whip it to make it fluffy again before frosting your cakes.
Can You Freeze Swiss Meringue Buttercream?
Made the frosting, then your plans changed? No worries! Swiss meringue buttercream freezes beautifully. Pop it in the freezer for up to three months. I’ve seen people say it keeps as long as six months, but my personal experience has maxed out at three months.
Thaw it completely in the refrigerator, then re-whip it before frosting.
Need More Frosting in Your Life? We Get It!
- Vegan Chocolate Frosting
- Easy Vanilla Buttercream
- Extra Rich Chocolate Frosting
- Cream Cheese Frosting
- Swiss Meringue Frosting
Chocolate Swiss Meringue Buttercream
- 5 egg whites
- 1 3/4 cup (367 g) granulated sugar
- 1 1/2 cup (3 sticks) unsalted butter, softened
- 10 ounces bittersweet chocolate, melted
- 1 teaspoon vanilla extract
- 1/4 teaspoon kosher salt
Melt the chocolate:
In a medium saucepan set over low heat, add the chopped chocolate, stirring it every 30 to 60 seconds to prevent it burning and allowing it to melt evenly. This should take about 8 minutes.
Heat the eggs and sugar:
In a small saucepan, add the 3 inches of water and set the pan over medium heat. Bring the water to a simmer. Place the egg whites and sugar in a large metal or glass bowl (I just use the bowl from my stand mixer). Set it over the pan of simmering water.
Make sure the bottom of the bowl doesn’t come in contact with the water. You just want the steam to gently heat it.
Whisk continuously until the sugar has dissolved completely. It will transform from thick and gelatinous to grayish-white, and finally thickened white and slightly frothy.
Check to see if the sugar has dissolved by dipping your finger into the egg mixture and rubbing it between your finger and thumb. If it feels smooth and silky, it’s ready.
Whip the egg whites and sugar:
Remove the bowl from the heat and whip the mixture on high speed until it has cooled completely. This will take about 10 to 12 minutes. When ready, the mixture will look like marshmallow fluff.
Add the salt and extract:
While the mixture is whipping, add the salt and extract.
Whip in the butter:
Add the butter one tablespoon at a time until incorporated. The mixture will look glossy and turn slightly yellow, then fluff up again.
Add the chocolate:
Fold the melted chocolate into the egg white mixture just until incorporated. Then whip it on high for about 3 to 4 more minutes. The mixture should look thick, fluffy, and the whisk will leave lines in it.
Frost your cake:
Frost your cake as you see fit. Use the back of a spoon to create swoops and swirls, or scoop it into a piping bag for cupcakes or decorative embellishments on the cake.