Preheat oven to 350°F. Lightly grease 2-3 donut pans (depending on the size) with cooking spray. Set aside.
Prepare the cake mix according to package directions (you'll likely need to add oil, egg, and water).
Spoon the mixture into a large ziplock bag and cut tip of bottom corner. Pipe the mixture into prepared donut pans, filling just over 3/4 of the way full.
Bake for 8-10 minutes, or until donuts are slightly firm and toothpick inserted into center comes out clean. Let cool in pan for 15 minutes and then remove to a wire rack to cool completely.
To prepare frosting, in a medium bowl, melt the chocolate frosting in the microwave for about 30 seconds, or until almost liquid-y.