This recipe follows the same amounts, etc as the vanilla recipe below. The only additional ingredient:
6-oz unsweetened baking chocolate, melted as pkg directs and cooled
Beat the butter in a medium mixer bowl until creamy with mixer on medium speed. Beat in the melted, cooled chocolate and marshmallow cream until blended. Beat in the powdered sugar and vanilla extract; increase mixer speed to high and beat an additional 3 to 4 minutes until fluffy.
Frost your favorite cake or cupcakes.