Step 1

Heat oven to 350°F.

Step 2

Prepare cake batter and bake as directed on package for 13x9-inch cake. Immediately poke deep holes in cake at 1-inch intervals, using round handle of wooden spoon.

Step 3

Beat pudding mixes and milk in medium bowl with whisk 2 min. Immediately pour over warm cake. Refrigerate 1 hour.

Step 4

Microwave chocolate and COOL WHIP in microwaveable bowl on HIGH 1-1/2 min. or until chocolate is almost melted, stirring after 1 min. Stir until chocolate is completely melted and mixture is well blended. Let stand 15 min. Pour over cake.

Step 5

Refrigerate 1 hour.