1. Line tray or cookie sheet with wax paper.
2. Drop one level measuring teaspoon of chocolate spread or peanut butter chocolate spread on center of flat side of cracker. Gently press flat side of second cracker on top (do not press spread out to cracker edges) making a sandwich. Repeat with remaining crackers.
3. Place milk chocolate chips and shortening in small deep microwave-safe bowl. Microwave at MEDIUM (50%) 1 minute; stir. If necessary, microwave at MEDIUM an additional 10 seconds at a time, stirring after each heating, until chips are melted and smooth when stirred.
4. Drop cracker sandwiches, one at a time, into melted chip mixture. Gently push cracker into mixture so that it is covered completely. (If mixture begins to thicken, reheat 10 to 20 seconds in microwave.) Using a fork, remove cracker from mixture. Tap lightly on edge of bowl to remove excess chocolate. Place on prepared tray. Immediately sprinkle top with nonpareils or sprinkles, if desired. Repeat for all cracker sandwiches. Refrigerate until chocolate coating hardens (about 20 minutes). For best results, store tightly covered in refrigerator. Makes 12 cracker sandwiches.