In 1-quart saucepan, combine chocolate chips and shortening. Cook over low heat, stirring occasionally, until melted and smooth. Loosen top paper cup from stack, but leave in stack for greater stability while being coated.
With a small paint brush, coat inside top cup evenly with about 1 teaspoon of melted chocolate to about 1/8-inch thickness, bringing coating almost to top of cup, but not over edge. Repeat until 30 cups are coated; refrigerate cups.
In a 2-quart saucepan, combine butter and peanut butter. Cook over medium heat, stirring occasionally, until melted. Stir in confectioners’ sugar and graham cracker crumbs.
Press about 1/2 tablespoon of filling into each chocolate cup. Spoon about 1/2 teaspoon of melted chocolate on top of filling; spread to cover.
Freeze until firm, about 2 hours. Store refrigerated.
