Preheat oven to 350°F

Prepare cake batter as directed on box.

Let cupcakes cool completely

Beat pudding mix and milk with whisk for minutes. Let stand 5 minutes.

Cut cupcakes in half horizontally

Whip 1/2 cup cool whip into pudding

Spoon mixture onto bottom half of cupcakes, about 1 tbsp.

Cover with tops

Microwave remaining cool whip and chocolate on high for 1-1/2 minutes

Stir until blended. Let stand 15 minutes

Spread on top of cupcakes

Refrigerate 15 minutes