Line 13x9-inch pan with foil, with ends of foil extending over sides; spray with cooking spray. Microwave unsweetened chocolate and butter in large microwaveable bowl on HIGH 2 min. or until butter is melted. Stir until chocolate is completely melted.
Add sugar; mix well. Blend in eggs and vanilla. Stir in flour until well blended.
Spread onto bottom of prepared pan.
Bake 30 to 35 min. or until toothpick inserted in center comes out with fudgy crumbs. (Do not overbake.) Cool in pan.
Spread jam over brownies. Microwave semi-sweet chocolate and cream in microwaveable bowl on HIGH 2 min. or just until mixture comes to boil. Stir until chocolate is completely melted and mixture is well blended; spread over jam layer. Refrigerate 1 hour or until chocolate layer is firm. Use foil handles to lift dessert from pan before cutting to serve.