Preheat oven to 350ºF.
Spray 8-inch square pan with vegetable cooking spray. Beat
together margarine and sugars until creamy. Beat in bananas,
egg, and vanilla.
Stir in melted chocolate. Stir in flour and salt until blended,
then fold in peanuts and chocolate chips. Pour mixture into
prepared pan. Bake 25 to 30 minutes or until brownies pull
away from side of pan (do not overbake). Cool completely
on wire rack. Prepare Chocolate-Peanut Butter Frosting;
spread over brownies. Chill for 5 minutes or until set.
Cut into sixteen squares. Cover and store in a cool place.
Chocolate-Peanut Butter Frosting: Melt together,
over medium heat, 1/2 cup semi-sweet chocolate chips and
3 Tbsp. creamy peanut butter.