Preheat oven to 350F and grease a 9×13-inch cake pan or baking dish. Set aside.
In a medium mixing bowl, combine cake mix, chocolate pudding mix, and milk. Use an electric mixer to beat together until nice and smooth.
Add 3/4 cup of chocolate chips to the batter and stir until incorporated.
Spread the batter into the prepared cake pan. Sprinkle the remaining 1/4 cup of dark chocolate chips over the batter. Bake in preheated oven for about 25-30 minutes, or until a toothpick inserted in the center of the cake comes out clean.
Remove from oven and let cool slightly before serving (can be served warm or cooled).
Notes
This cake is delicious on its own, but we especially love to top it with a dollop of Cool Whip (use reduced fat if needed). I prefer to enjoy it warm, so even after the cake is cooled, I often microwave a slice so the chocolate chips are nice and melty.
By itself, devil's food cake mix is extremely low fat (since we aren't adding eggs or oil), and most chocolate instant pudding mix is fat free. You can use low fat or skim milk in this recipe. Most of the fat is in the dark chocolate chips, so you can decrease or omit those if necessary.
Cover leftovers and store at room temperature for up to 3-5 days.