Chocolate Peanut Butter Bars

This may well be the most unhealthy thing I've posted so far. But it's good. It's a quick to fix crowd pleaser. And you'd be wise to only make them for a crowd, lest you eat them all yourself.
INGREDIENTS
2 1/2 cups graham cracker crumbs
1 cup peanut butter
1 cup butter, melted
2 cups powdered sugar
Topping
1 1/2 cups chocolate chips
1/4 cup peanut butter
DIRECTIONS
In a medium bowl, stir together graham cracker crumbs, confectioners' sugar, peanut butter and melted butter. Press firmly into the bottom of a 9x13 inch pan. Melt chocolate chips and peanut butter over a double boiler or in the microwave, stirring occasionally. Spread melted chocolate over the crumb crust. Chill for about 20 minutes, then cut into bars, then chill until ready to serve.