Preheat oven to 375.
Chop apple into small pieces and set aside.
Add oatmeal, protein powder, cinnamon, salt, baking powder to mixing bowl and stir to combine thoroughly.
In another mixing bowl, add applesauce, milk, egg and maple syrup and stir to combine.
Add dry ingredients into the liquid ingredients and mix to combine.
Stir the chopped apples into the oatmeal mixture.
Coat an 8 X 8 baking dish with nonstick cooking spray.
Pour oatmeal mixture into baking dish.
Bake at 375 for 30 to 35 minutes or until the edges are slightly browned and the top is set (should still be moist but not jiggly).
Remove from oven and allow to cool for about 5 minutes before cutting into 6 slices and serving.
Eat plain or add a topping of your choice (sugar free maple syrup, yogurt, protein frosting, cinnamon, sugar free brown sugar, etc).