The runner-up in buttercream popularity, at least in the US, is the meringue-based Swiss buttercream. This is my go-to fancy cake icing, which I'll explain in a later post. It's not nearly as sweet as the next kind, but has a light and silky texture that lends itself to more delicately flavored cakes.
The kind that most people have surely had is the American buttercream or "simple buttercream" -- butter, confectioner's sugar, a splash of milk or cream, and flavorings if desired -- for which the recipe is listed below. It's sweet and often forms a very thin hardened crust on the icing, found in most bakery cakes. And it's easy to make. Only one small appliance, four ingredients, and no heat or cooking involved.
Resist all urges to do anything to unnaturally soften the butter. If, like me, you bake when you get home from a day at work or school and can't stand the idea of waiting a few more hours for butter to soften, put out a stick of butter (still wrapped) on a plate somewhere in your kitchen. Yes, it's okay to leave butter out at room temperature. Our grandparents did it, so did our parents. No need to freak out over this. The reason for my rant is that if the butter isn't softened the whole way through, the icing will have tiny lumps of butter in it... not good. Now, without further ado...
-makes about 1 3/4 cups or enough for 15 regular cupcakes with extra for snacking
1 stick unsalted butter, room temperature
1/2 tsp vanilla extract
3-4 cups confectioner's sugar
1/4 cup milk
In the bowl of an electric mixer fitted with the paddle attachment, cream butter until smooth and creamy, 2 to 3 minutes. Really mix here... you're looking for silky butter here. With mixer on low speed, add 3 cups confectioner's sugar, milk, and vanilla; mix until light and fluffy (2-3 more minutes). If necessary, gradually add remaining 1 cup sugar to reach desired consistency. (I usually use about 3 1/2 cups total, but it's up to you if you like a stiffer or softer icing.) If you'd like to color your icing, now is the time to add food coloring... one drop at a time.
Top your favorite cake or cupcakes with this nectar of the gods. You won't be disappointed!