Butercream frosting is my favorite of all. Typically you would measure three cups of confectioners sugar into a mixing bowl, a splash of vanilla extract, a softened stick of butter. Add a small amount of cream, or half and half or milk, usually a few tablespoons or so. Whip it good. The whipping incorporates air and makes your frosting creamy. Variations are adding cream cheese, you can reduce the amount of butter then. Earlier today I made a peanut butter cream cheese frosting. If you don't want vaniila, you may add other flavoring agents instead.