Lightly spray microwavable mug (8 to 10 oz) with cooking spray.
In small bowl, beat cake mix, water, applesauce and egg. Fold in 1 teaspoon sprinkles; immediately pour into mug.
Microwave uncovered on High 1 minute. Cake is done when toothpick inserted in center comes out clean. Let stand 5 seconds.
Top with frosting, additional sprinkles and cherry. Serve immediately.
