This buttercream recipe is small batch and so quick to make. It packs a punch in vanilla flavor and makes 1 cup of frosting, enough to cover the top of one 13-by-9-inch sheet cake.
In a mixer bowl fitted with the paddle attachment, whip the butter until light and fluffy.
Alternately add the confectioners' sugar and milk (or water), scraping and mixing well after each addition. Add the vanilla extract and allow buttercream to whip for an additional 3-5 min, until fluffy.