Crispy Marshmallow Brownies

1 brownie mix (9x13 size)
1 10-1/2-oz package tiny marshmallows
1-1/2 cups chocolate chips
1 cup peanut butter
1 tablespoon butter
1-1/2 cups Rice Krispies cereal

Prepare the brownie mix according to package directions, making chewy (not cakelike) brownies.

Bake according to directions and top brownies with the marshmallows during the last 3 to 5 minutes of baking or until golden. Cool in the pan on a wire rack.

In a saucepan, combine chocolate pieces, peanut butter, and butter. Heat and stir until the chocolate is melted. Remove from heat; stir in the cereal. Pour evenly over marshmallows.

Refrigerate until topping is set. Cut into bars.