Slightly modified version of a recipe in Everyday Food magazine. This cake is SO good, especially while it's still warm (or reheated). Great for breakfast. Or topped with whipped cream or vanilla ice cream. I choose Granny Smith apples for their tartness and because they hold their shape after baking. The apples come out completely soft after baking. I love the tartness of the apples mixed with the sweetness of the cake. Optional: Add 1/2 cup chopped walnuts if desired. Note: The original recipe called for 1/2c of butter, but I reduced that to 1/4 and added in 1/4 applesauce to lower the fat in the recipe. You won't even miss the extra butter at all.