In a large mixing bowl, combine the peanut butter, butter, crushed graham crackers, and confectioners’ sugar until well mixed.

Press the mixture into a buttered 13x9x2-inch baking dish, spreading it out evenly.

In a microwave-safe bowl, melt the chocolate chips in the microwave in 30-second intervals, stirring in between, until smooth.

Spread the melted chocolate evenly over the top of the peanut butter mixture in the baking dish.

Chill the bars in the refrigerator for about 1 hour, or until the chocolate is set.

Once chilled and set, cut the bars into squares before serving.