Very Best Swiss Meringue Buttercream

I've always been a huge fan of Swiss Meringue Buttercream because it's less sweeter than the American Buttercream. It's just as easy too! Below is the recipe that I've been using for a while and it's definitely a keeper. Sometimes I'll add peanut butter and that turned out fantastic as well.

Swiss Meringue Buttercream

(Source: Food Network)

6 large egg whites, at room temperature

1 cup sugar

1/4 teaspoon salt

4 sticks unsalted butter, cut into small pieces, at room temperature

2 teaspoons pure vanilla extract

Bring a few inches of water to a simmer in a medium saucepan over medium heat. Whisk the egg whites, sugar, and salt in the bowl of a stand mixer.Set the bowl on top of the pan (do not let the bottom of the bowl touch the water). Cook, whisking, until the egg whites are frothy, the sugar dissolves and the mixture is warm, 3 to 5 minutes. 

Transfer the bowl to the stand mixer and beat with the whisk attachment on medium-high speed until the mixture is cool and stiff glossy peaks form, about 5 minutes. Beat in the butter a few pieces at a time, waiting until they're incorporated before adding more. The frosting may look liquidy or curdled but just keep beating until smooth and shiny. Add the vanilla and beat until fluffy, 3 to 5 more minutes.