Swiss Meringue Buttercream is the BEST in the world of buttercream! This frosting is light and fluffy, silky smooth and creamy, and super stable for decorating cakes and cupcakes.
When it comes to ease and simplicity, American buttercream wins.
But when it comes to taste and texture, nothing beats Swiss meringue buttercream!
What is Swiss meringue buttercream?
Swiss meringue buttercream is a buttercream frosting made with Swiss meringue and butter, plus other flavorings like vanilla.
Swiss meringue is made of egg whites and sugar cooked in a double-boiler (Bain Marie), then whipped into fluffy meringue.
This buttercream is an ideal frosting for decorating cakes, cupcakes and even macarons!
Why you’ll love this recipe?
- Simple ingredients: only 5 basic ingredients
- Incredible texture: light, fluffy, creamy, silky sooth
- Balanced taste: not too sweet, not overly buttery
- Easy to use: perfect consistency for piping and frosting
- Easy to make: with few key tips for success
How to make Swiss meringue buttercream:
Step 1. Make Swiss Meringue
- In a heat-proof bowl, combine sugar and egg whites together. And place the bowl over simmering water.
- Cook the egg whites gently until it reaches 160°F, whisking it continuously. (This’s my favorite thermometer!) You shouldn’t feel any sugar granules when you rub the mixture between your fingertips.
- Now remove from heat and whisk it until stiff peaks form. At this point, meringue should be completely cooled.
3 tips for successful meringue:
- Make sure the bowl and whisks are completely grease free. It’s ideal to use stainless steel or glass bowl for making meringue.
- Never break the eggs over your main egg white bowl. Instead, use this 3-bowl method: 1 bowl for collecting egg whites, 1 for egg yolks, and 1 for breaking and separating each egg.
- Be careful when separating egg whites. You should have even smallest amount of yolk in the egg whites. Here’s why.
It’s easier to separate cold eggs right out of the fridge, because egg yolk is firmer.
Step 2. Add butter
- Add room temperature butter, one tablespoon at a time, whisking the frosting thoroughly after each addition.
- Continue whisking the buttercream until all the butter is added and the frosting is super light and fluffy.
ROOM TEMPERATURE BUTTER
It’s important to use room temperature butter. When you push a finger into it, the butter should dent with some resistance.
- Too soft butter will cause soupy frosting.
- Too cold butter will curdle the buttercream.
How to bring butter to room temperature?
Take the butter out of fridge 1-2 hours before making the frosting. Butter at room temperature should be cold to touch and dent when pressed without losing its shape.
If you forgot to take butter out in advance (happens to all of us), here’s a genius trick to quickly soften butter.
Step 3. Add vanilla
Switch to paddle attachment and add vanilla extract, or vanilla bean paste.
You can also add food coloring at this stage. It’s best to use gel food coloring.
For ultra-smooth buttercream, beat the buttercream with paddle attachment on low speed to remove excess air pockets.
Is Swiss meringue buttercream safe to eat?
Since we’re cooking egg whites in a double boiler until it reaches 160°F, it’s completely safe to eat. We basically pasteurized the egg whites.
To be safer, I highly recommend using an instant thermometer to make sure egg whites had reached the proper temperature!
Can I add flavors?
Absolutely! You can substitute any extracts for vanilla extract. Also, check out my Chocolate Swiss Meringue Buttercream and Salted Caramel Buttercream.
Can I add food coloring?
Yes, I recommend using gel food coloring.
Can I use carton egg whites?
I’ve used carton egg whites with great success. Be sure to read the labels, as some carton egg whites specify that it’s not for meringue.
Can I make it without a thermometer?
For food safety, I strongly recommend using a thermometer to ensure the eggs reach 160°F. If using pasteurized (carton) egg whites, you can skip a thermometer. But be sure the sugar is completely dissolved, you don’t feel any sugar granules between your fingers.
How do you make white Swiss meringue buttercream?
If your buttercream has yellowish hue, add very small amount of violet gel food coloring. I use a toothpick to smear tiny bit of color. And then whip it well.
Troubleshooting Swiss Meringue Buttercream
Meringue won’t reach stiff peaks
This could happen if the egg whites were in contact with any fat, grease, or egg yolks. Make sure to clean your bowls and whisks thoroughly, wipe the utensils with vinegar or lemon juice, if needed. And be careful when separating egg whites and yolks.
I’ve encountered this issue with carton egg whites couple of times. I added butter into soft meringue, and buttercream turned out just fine! So if you got soft meringue and it’s not stiffening up, go ahead and add butter as per instructions.
If your buttercream starts to curdle in the process of adding butter, or right after adding all the butter, don’t panic. It’s totally normal. To fix: just continue beating! And I promise, it’ll magically come together at the end.
And if it doesn’t, simply place the bowl with buttercream over simmering water. Let the buttercream melt a little around the edges, then try whipping it again.
It happens when the meringue was still warm when you started to add butter. Or the butter was too soft and started to melt in the meringue. To fix: place the bowl with buttercream in the fridge for 15-30 minutes, and then whip it again.
Tastes too buttery
When done right, Swiss meringue buttercream is super light, fluffy, and silky smooth. If your buttercream is thick and heavy, it just needs more whipping.
Make Ahead Direction:
Swiss meringue buttercream is an ideal frosting to make in advance. Here’re 3 ways to store it:
- On the counter: It’s ok to keep Swiss meringue buttercream at room temperature for overnight. (It has enough sugar and fat to keep it from spoiling!)
- Refrigerator: You can refrigerate this buttercream in an airtight container for up to 2 weeks.
- Freezer: Swiss buttercream also freezes well. It’ll freeze well in airtight container for up to 3 months!
Thaw frozen buttercream on the counter overnight. Whip it before using.
Swiss Meringue Buttercream
- 6 egg whites (Note 1)
- 1 ½ cups (300g) granulated sugar
- ½ teaspoon coarse kosher salt
- 1 ½ cups (340g) unsalted butter, softened and cubed (Note 2)
- 1 vanilla bean split and scraped (or 1 teaspoon vanilla bean paste)
- In a small saucepan, bring a small amount of water to a boil. Reduce the heat to simmer.
- In medium heat-proof bowl (I used my stand mixer bowl), whisk together egg whites and sugar and place it over the saucepan with simmering water. (This is a make-shift double boiler. Make sure the bottom of the top bowl doesn’t touch the water.)
- Cook the egg white mixture until sugar is completely melted and it reaches 160°F (70°C) stirring continuously, about 5 minutes. (This's my favorite thermometer!)
- Now, remove the bowl with egg white mixture from heat. Then whisk it on medium speed for a minute, then slowly increase the speed to medium high and beat until stiff peaks form and the mixture is cool to touch, about 10 minutes. (It may take longer with a hand-mixer.)
- Once the meringue reached stiff peaks, scrape the side of the bowl with a spatula and add salt.
- Turn on the mixer on medium speed and start adding butter, one tablespoon at a time. Make sure the butter is fully incorporated before adding the next piece. (NOTE: It’s normal if buttercream starts to curlde half way. Keep adding the butter!)
- Keep whisking the buttercream until smooth, light and fluffy, about 10 minutes.
- Now, switch to a paddle attachment and add vanilla bean. Beat the buttercream until well combined, about a minute.
Tips & Notes:
Swiss meringue buttercream can be made in advance and frozen for up to 3 months, or refrigerated for up to 2 weeks. Thaw the frozen buttercream on the counter overnight. Whip it before using. Note 1: While I’ve had success with carton egg whites, not all brands work for meringue. But if you want to try, you’ll need 210g of liquid egg whites. Note 2: Make sure the butter isn’t too soft. When you push a finger into it, the butter should dent with some resistance.