MICROWAVE margarine and 3 Tbsp. peanut butter in microwaveable bowl on HIGH 30 sec. or just until melted. Stir in graham crumbs and sugar; press onto bottoms of 24 paper-lined mini-muffin cups.
COMBINE Cool Whip and 1/2 cup of the remaining peanut butter; spoon into muffin cups.
MICROWAVE chocolate and remaining peanut butter in microwaveable bowl on MEDIUM 1 min.; stir. Spread over desserts.
REFRIGERATE 30 min. or until chocolate is firm.
serving size = 2 dessert cups (18 g)