• Line an 8x8-inch pan with foil or parchment paper and set it aside.

MAKE THE PEANUT BUTTER LAYER:

• In a medium bowl, mix the melted butter, graham cracker crumbs and powdered sugar. Stir in 1 cup of peanut butter, then press the mixture evenly into the prepared pan.

MAKE THE CHOCOLATE LAYER:

• In a small bowl melt the chopped chocolate and 3 tablespoons peanut butter in the microwave or on the stove in a double boiler. Stir until smooth. Spread evenly over the peanut butter layer.
• Chill the bars in the refrigerator until completely firm, at least 2 hours. Allow them to sit at room temperature for 10 minutes before cutting. Served chilled. (Setting them out for a few hours at room temperature for serving is OK).
• Cover leftover bars tightly and refrigerate for up to 1 week.