Preheat oven to 350 F. Meanwhile, peel, core, and cube the apples into ½ inch-sized cubes then place in a greased 9×13-inch baking pan or any 4-quart baking dish.
To the apples, add all the listed ingredients and mix well. You can even use your hands.
In another bowl, mix the flour, oats, brown sugar, and cinnamon. Then, add the cubed 1 stick of softened butter and mix well. You can even use your hands.
Evenly sprinkle the mix on top of the apples. This is optional, you can add additional cubed butter to the top of the oat mix.
Bake for about 45 minutes. Enjoy warm with ice cream.
Video
Notes
For a lighter version you can swipe the butter for coconut oil, the flour for oat flour and the sugar for honey or maple syrup!