1. Rinse apples, wipe dry, and firmly insert a stick into stem end of each fruit until secure.
2. In a 1-quart glass measure or small deep microwave-safe bowl, combine candy and shortening. Place in a microwave oven and heat at half power (50%) until chips are soft, 2 1/2 to 3 minutes. Stir until smooth. If still lumpy, return to microwave and heat for 20-second intervals until candy is smooth.
3. Quickly dip apples, 1 at a time, into coating to cover, letting excess drip back into bowl. Set apples, sticks up, in a 10- by 15-inch pan lined with waxed paper or cooking parchment. If desired, make ghost faces by pressing licorice slices into soft coating. If coating on apple is too firm, use melted coating to glue licorice in place. If coating gets too thick, reheat it briefly in the microwave at 50% power and stir.
4. Let apples stand until coating is firm to touch, at least 30 minutes at room temperature or 10 minutes if chilled.