In medium microwavable bowl, microwave black candy melts and 4 teaspoons of the shortening uncovered on Medium (50%) 1 minute, then in 15-second intervals, until melted; stir until smooth. Repeat with green candy melts and remaining 2 teaspoons shortening. Dip tip of 1 lollipop stick about 1/2 inch into melted black candy and insert stick into 1 cake ball no more than halfway. Repeat. Return to cookie sheet. Refrigerate 5 minutes. Remove from refrigerator a few at a time. Dip cake balls in black candy (do not tap off excess). Place cake balls, tops down, on cookie sheet. Let stand until set.