1Heat oven to 350°F. Place paper baking cup in each of 24 regular-size muffin cups or spray with cooking spray. Make and bake cake mix as directed on box for cupcakes, using water, oil and eggs. Cool 10 minutes; remove from pans to cooling racks. Cool completely, about 30 minutes.
2Spoon frosting into medium bowl; tint with purple food color. Frost cupcakes. Sprinkle with sanding sugar. Top with rock candy. Cut out each snack cake to look like crescent moon. Garnish cupcakes with moon cutouts.