Line a 13- X 9-inch baking pan with non-stick aluminum foil (for easier removal) or simply butter the pan.

Combine cereal and peanut butter chips in a large bowl.

Melt butter in a medium saucepan over medium-low heat. Add marshmallows and cook, stirring constantly, until marshmallows have completely melted and mixture is thoroughly combined.

Add peanut butter and continue to cook and stir until combined and smooth.

Pour melted marshmallow mixture over cereal and stir to coat completely.

Press mixture into prepared pan. I used another piece of non-stick foil to easily press it down without sticking.

Cool to room temperature. Cut into 24 squares.