This Low Calorie Applesauce Cake is just 109 calories, and low in sugar! I made these really big slices, but you could cut them into 8 squares and the calories would go down to 82 calories. Special Tip: If you don't have oat flour, you can make your own. Just add old fashioned oatmeal to a food processor or high speed blender and pulse until you have a fine flour list substance.