In a large bowl, whisk together cake mix, egg, water and oil until completely combined. Pour into small (ungreased) pan provided in cake kit. Place in oven and bake for 28-33 minutes or until a toothpick inserted in middle of cake comes out clean. Let cool.
Massage the bag of frosting the comes with the kit. Cut a corner of bag and squeeze onto cake. Spread with a butter knife or offset spatula. Add sprinkles. Serve and enjoy!
Notes
For nutrition facts, check the package of the Duncan Hines Easy Cake Kit.