This quadruple-layer cake isn't nearly as fussy to make as you might think. It starts out as a standard two-layer cake, then each layer is cut in half and stacked, with an easy filling in between the layers. The result is a moist cake that keeps well without refrigeration; looks spectacular when cut, and tastes even better than it looks! Want to make 2 dozen cupcakes instead of a layer cake? See our recipe Favorite Fudge Birthday Cake with 7-Minute Icing.