Preheat the oven to 350°F (175°C) and line a baking tray with parchment paper.
Combine dry ingredients – In a large mixing bowl, add the ground oat flakes, whole oat flakes, and cinnamon. Mix well.
Prepare wet ingredients – Mash the banana, then mix it with the chopped apple and coconut oil.
Combine wet and dry ingredients – Stir the wet ingredients into the dry mixture until everything is well incorporated. Fold in the nuts or almonds.
Shape and Bake – Form small cookies or spread the mixture into a baking dish for oat bars. Bake for 15-20 minutes until golden brown and firm.
Cool and Enjoy – Let them cool before serving. Enjoy as a healthy breakfast, snack, or pre-workout meal.