Prepare your brownies. When they have about 8 minutes of baking left, pour the marshmallows over the top and finish cooking until they're golden brown. Let cool while you prepare the topping.

For the topping, combine the chocolate chips, peanut butter, and butter in a microwave safe dish. Microwave thirty seconds at a time, stirring at each interval, until smooth and melted. Fold in the Rice Krispies and then pour over the brownies.The end.