MELT 2 Tbsp. butter; mix with cookie crumbs. Reserve 2 Tbsp. crumb mixture; press remaining onto bottom and up side of 9-inch pie plate.
MICROWAVE chocolate and remaining butter in microwaveable bowl on MEDIUM 1 min. or until butter is melted. Stir until chocolate is completely melted and mixture is well blended; spread onto bottom of crust. Top with bananas.
BEAT pudding mix and milk with whisk 2 min.; pour over bananas. Refrigerate 4 hours. Top with COOL WHIP and reserved crumb mixture.