In a large bowl, combine peanut butter, confectioners' sugar, graham cracker crumbs, and butter. Mash together until combined. Form the mixture into balls. Transfer to the refrigerator until hardened, about 30 minutes. Dip the peanut butter balls into the melted chocolate and set inside mini paper cupcake forms. Let the chocolate set before serving.

Peanut Butter: In the bowl of a food processor, grind the peanuts until smooth. With the motor of the food processor running, add peanut oil if necessary, and puree until the peanuts are the consistency of peanut butter.