Marshmallow Krispie Bars

1

1 (21-ounce) Family-size brownie mix

1 package (10 ½ ounces) miniature marshmallows

1 ½ cups semisweet chocolate chips

1 cup creamy peanut butter

1 tablespoon butter or margarine

1 ½ cups crisp rice cereal

1. Preheat oven to 350 degrees F. Grease bottom only of pan of 13x9-inch pan.
   
2. Prepare and bake brownies following directions for cake-like recipe. Remove from oven. Sprinkle marshmallows on hot brownies. Return to oven and bake for 3 minutes longer.
   
3. Place chocolate chips, peanut butter and butter in medium saucepan. Cook over low heat, stirring constantly, until chips are melted. Add rice cereal; mix well. Spread mixture over marshmallow layer. Refrigerate until chilled. Cut into bars.