Preheat your oven to 350°F (175°C). Lightly grease a small oven-safe baking dish with cooking spray or a touch of softened butter.
Sauté the apples: In a small skillet, warm the coconut oil over medium heat. Add your chopped apple pieces and a dash of cinnamon. Sauté for about 3-5 minutes until the apples are tender and soft. Set them aside.
In a blender, first process your dry oats until they turn into a fine powder.
Next, add the baking powder, ½ teaspoon cinnamon, vanilla extract, vanilla protein powder, nutmeg, and unsweetened almond milk to the blender. Blend until all ingredients are well combined and the batter is smooth.
Pour half of the oat batter into your prepared baking dish. Evenly spread half of the sautéed apples over this layer. Gently pour the remaining oat batter on top, then scatter the rest of the sautéed apples and your optional granola or nuts over it.
Bake in the preheated oven for 20-25 minutes, or until the top is golden brown and the oatmeal is set.
Carefully remove from the oven. Enjoy your warm, nutritious, and easy breakfast!