MIX cookie crumbs and butter; press onto bottom of 8-inch square pan.
ADD milk gradually to peanut butter in large bowl, stirring with whisk until well blended. Add dry pudding mixes; beat 2 min. (Mixture will be thick.) Stir in 1 cup COOL WHIP. Spread onto crust; cover with remaining COOL WHIP.
REFRIGERATE 3 hours or until firm. When ready to serve, microwave fudge topping as directed on package; drizzle over dessert. Top with peanut butter pieces.