Gather all ingredients.

Mix together graham cracker crumbs, confectioners’ sugar, butter or margarine, and 1 cup peanut butter in a medium bowl until well-blended.

Press evenly into the bottom of an ungreased 9x13-inch pan.

Place chocolate chips and 4 tablespoons peanut butter in a microwave-safe bowl. Microwave on high, stirring every 15 seconds, until smooth.

Spread mixture over crust.

Refrigerate for at least 1 hour before cutting into 12 squares.