Line cookie sheet with waxed paper. In small microwavable bowl, microwave chocolate chips and shortening on High 1 1/2 to 2 minutes or until melted; stir until smooth. To make tops of witch hats, dip snacks, one at a time, into melted coating, letting excess drip off. Place point up on cookie sheet. Let stand until coating is set.
Prepare white chocolate pudding with 2 cups of the milk as directed on box. Prepare chocolate fudge pudding with remaining 2 cups milk as directed on box. Stir green food color into white chocolate pudding until well blended.
For each pudding cup, spoon 2 tablespoons of the green pudding into bottom of 4-ounce clear plastic cup or serving dish; top with 2 tablespoons of the chocolate fudge pudding. Repeat with each flavor to form four layers. With handle of spoon, gently swirl the two top layers. Insert cookie in pudding; top with chocolate-coated Bugle® to resemble witch hat. Insert tip of pretzel stick into pudding with a few pieces of cereal sprinkled at the base to resemble a broom. Insert ends of 2 gummi worm candies into pudding and hang over edge to resemble the witch’s legs.