In medium microwavable bowl, mix chocolate chips, butterscotch chips and remaining 1/2 cup peanut butter. Microwave uncovered on High for 1 to 2 minutes, stirring once, until melted. Stir in peanuts. Spread evenly over cookie bars. Refrigerate about 1 hour or until chocolate is set. For bars, cut into 8 rows by 4 rows.