HEAT oven to 325ºF.
LINE 13x9-inch pan with foil, with ends of foil extending over sides. Mix cookie crumbs and butter; press firmly onto bottom of pan. Bake 10 min.
BEAT cream cheese, sugar and vanilla in large bowl with mixer until well blended. Add sour cream and chocolate; mix well. Add eggs, 1 at a time, beating after each just until blended. Pour over crust.
BAKE 40 min. or until center is almost set. Cool. Refrigerate 4 hours. Lift cheesecake from pan, using foil handles. Top with COOL WHIP and pie filling.