frosting for one 9-inch square cake
1/2 cup firmly packed brown sugar
2 tablespoons cocoa
1/4 cup water
1 1/2 cups sifted powdered sugar
3 tablespoons butter or margarine
1 teaspoon vanilla extract
Combine brown sugar, cocoa, and water in a medium saucepan; bring to a boil, stirring constantly. Boil 2 minutes. Remove from heat; stir in remaining ingredients. Beat until mixture is of spreading consistency.