Peanut Butter Cups

1 cup Butter or Margarine
1 cup Peanut Butter
1 pound Powdered Sugar
1 1/2 packages Graham Crackers -- (crumbs)
12 ounces Chocolate Chips

Melt butter in saucepan over low heat. In a large mixing bowl, mix all ingredients except chocolate chips, kneading to make a soft dough. Spread mixture onto a cookie sheet, then top with melted chocolate chips. Chill until firm, then cut into squares.