Preheat the oven to 350 degrees F. Grease a cast iron skillet, deep pie pan, or 9×9 pan and set it aside.
In a very large bowl, add the prepared apples, cinnamon, nutmeg, coconut sugar, vanilla, lemon, and cornstarch. Stir with a spatula or spoon until everything is evenly combined. Add the apples to the greased cast iron skillet, deep pie pan, or 9×9 pan. Make sure it’s packed in there. It will shrink a lot after it’s baked and cooled.
In that same bowl, add all the topping ingredients. Stir until well combined. Sprinkle topping evenly over the top of the apples, then using your hands to press it down.
Bake 50-60 minutes, until apples are tender when poked with a fork or knife and the topping is golden brown. Mine took about 55 minutes.
Let it cool for one hour before serving. Enjoy warm! Although best when fresh, keep leftovers in an airtight container in the fridge for up to 3-4 days. Reheat in the microwave for 30 seconds or until warm.