There's a recipe for Darn Good Chocolate Cake in "The Cake Mix Doctor" cookbook that I make that always goes over well. You add chocolate pudding, sour cream, and chocolate chips. The cake mix is so thick that the chips suspend throughout the cake. In "The Cake Mix Doctor", the instructions are for a bundt cake, but I make it up as a double layer cake using Duncan Hines cake mix and then frost with Duncan Hines chocolate frosting. It always gets eaten very fast.