Chocolate Frosting

1 Stick Butter (1/2 C)
2 C powdered sugar
4 tbsp cocoa
2 tbsp milk
1 tsp vanilla

Whip butter till smooth and creamy. Add sugar a little at a time. Add cocoa, milk and vanilla. Beat till creamy. Frost on cooled cake. Can refrigerate for later use. Let sit at room temperature before frosting.