Perfect Swiss Meringue Buttercream

This is vanilla Swiss Meringue Buttercream perfection. It’s the ideal balance of sweet and creamy, without being as cloyingly sugary as American buttercream. (This is a far cry from how sweet that is!) Thick, sturdy, and perfectly pipe-able. This in-depth recipe sets you up for success on your 1st try.

Ingredients

6 large egg whites (approximately 230g)
2 cups (400g) granulated sugar
1 and 1/2 cups (340g) unsalted butter, softened but still cool and cut into Tbsp size pieces (*see note*)
2 teaspoons pure vanilla extract
1/8 teaspoon salt

Instructions

Watch the video tutorial above, review the troubleshooting tips, and read the recipe in full before beginning. Make sure all the tools you are using are completely cleaned, dried, and grease-free. A quick wipe with a little lemon juice or white vinegar is very helpful.
Separate the eggs: If you haven’t done so yet, separate the eggs first. Separate 1 egg white in a small bowl, then place the egg white in your heatproof mixing bowl. Repeat with the remaining egg whites. This way, if a yolk breaks in one of them, you don’t waste the whole batch.
Whisk sugar into the egg whites, then set the bowl over a saucepan filled with just two inches of simmering water over medium heat. Do not let the bottom of the egg whites bowl touch the water. Whisk the whites and sugar constantly until sugar is dissolved and mixture has thinned out, about 4 minutes. The mixture will be thick and tacky at first, then thin out and be frothy white on top. To test that it’s ready, you can use your finger or an instant read thermometer. Lightly and quickly dip your finger (it’s very hot, be careful) and rub the mixture between your thumb and finger. You shouldn’t feel any sugar granules. If using a thermometer, the temperature should read 160°F (71°C).
No need to let it cool down to start this next step—it’s important to begin mixing while it is still warm. Transfer mixture to the bowl of a stand mixer fitted with a whisk attachment (if you aren’t already using the metal bowl that comes with it). You can use a hand mixer instead, but this step takes awhile and your arm tires