I assume this came off the can of Hershey Cocoa.
6 Tbsp. butter, softened
3/4 cup cocoa
2 2/3 cups unsifted confectioners sugar
1/3 cup milk
1 tsp. vanilla
Cream butter in a small mixer bowl. Add cocoa and confectioners sugar alternately with milk. Beat to spreading consistency. An additional tablespoon of milk may be needed. Blend in vanilla.
Yield 2 cups.