(1) Heat oven to 350, Make brownies as directed for 13X9 pan. Cool completely.
(2) Frost brownies with frosting. Refrigerate. Meanwhile, Into large bowl, measure cereal: set aside. In 1-quart saucepan, melt peanut butter and chocolate chips over low heat, stirring constantly. Pour over cereal in bowl, stirring until evenly coated. Spread over frosted brownies.
Refrigerate about 30 minutes or until set before cutting. Store covered in refrigerator. Can be taken out of pan and put on platter for serving.