Gluten-Free Mexican Hot Chocolate-Cereal Bars

Spray 13x9-inch pan with cooking spray. In large microwavable bowl, microwave butter uncovered on High about 45 seconds or until melted. Add marshmallows; toss to coat. Microwave 1 to 1 1/2 minutes longer. Stir until marshmallows are completely melted and mixture is well blended. Add cereals and red pepper; mix well. Using waxed paper or spatula sprayed with cooking spray, press mixture evenly in pan. Cool 15 minutes. In small microwavable bowl, microwave chocolate chips uncovered on High 30 to 60 seconds. Stir until smooth. Spoon melted chocolate into resealable food-storage plastic bag. Cut small corner off bag, and pipe chocolate on top of bars. Refrigerate 5 to 10 minutes or until chocolate is set. For bars, cut into 6 rows by 3 rows.