Line a 9x9 inch baking pan with aluminum foil and spray with non-stick cooking spray. Set aside.
Using a food processor or blender, pulse graham crackers until crumbly.
In a large bowl, mix graham cracker crumbs, melted butter, powered sugar, and 1 cup creamy peanut butter until mixture is well blended.
Press mixture into prepared pan.
In a microwave safe bowl, microwave milk chocolate chips and 3 Tablespoons creamy peanut butter until melted. Spread over top of peanut butter bars. Place bars in fridge for at least 1 hour or up to 1 day before cutting into squares.
Notes
LINE YOUR PAN:To make it super easy for you to cut these bars into squares, line your 9×9 inch baking pan with aluminum foil, leaving enough overhang on the sides and spray the foil with non-stick cooking spray. Once the chocolate peanut butter bars have chilled in the fridge for at least 1 hour, lift the bars out of the pan, folding down the aluminum foil sides. Then use a sharp knife to cut these bars into squares.