1/2 cup butter
1/3 cup milk
6 tablespoons unsweetened cocoa
1 (16-oz.) package powdered sugar
1 teaspoon vanilla extract
Cook first 3 ingredients over medium heat in a large saucepan, stirring constantly, 4 to 5 minutes or until butter melts. Remove from heat, and beat in powdered sugar and vanilla at medium speed with an electric mixer until smooth.