Crumble 1 cupcake; set aside for topping. With end of wooden spoon handle, make deep, 3/4-inch-wide indentation in center of top of remaining 23 cupcakes, not quite to bottom. Spoon pudding into resealable food-storage plastic bag; seal bag. Cut 1/2-inch tip off corner of bag. Insert tip of bag into opening in each cupcake; squeeze bag to fill opening. Frost cupcakes with ganache; sprinkle with cupcake crumbs. Store loosely covered.