1 hour 11 minutes
- Prepare cake batter and bake as directed on package for 24 cupcakes; cool completely.
- Meanwhile, cook 1 cup marshmallows, semi-sweet chocolate and milk in large saucepan on low heat until marshmallows and chocolate are completely melted and mixture is well blended, stirring constantly. Pour into large bowl; cool 30 min.
- Whisk COOL WHIP into marshmallow mixture; spread onto cupcakes. Top with remaining marshmallows and cocoa powder.