Preheat the oven to 350 F. Generously spray a muffin pan with non-sticking cooking spray. Or use silicon muffin liners.
Combine all the wet ingredients in a mixing bowl. Whisk the oats, apple spices and baking powder in a separate bowl. Add the dry ingredients in the wet ingredients, and mix well.
Fold in the apples and walnuts (if using any) with a spoon or rubber spatula.
Fill the greased muffin pan close to the top. Add extra apples and sprinkle of cinnamon on top if you like.
Bake 25 minutes or until tooth pick come out clean.
Last but not least, take the oatmeal cups out of the muffin cups once they cooled down.
Enjoy!
Notes
* For sweetener option, add the additional coconut sugar.