Preheat your oven to 375°F
Wash and core the apples. If you don’t have an apple corer, use a paring knife, carefully cutting around the core without piercing the bottom. This prevents losing the delicious juices during baking. Widen the top opening slightly to hold more filling.
In a medium-sized mixing bowl, combine oats or chopped nuts, raisins, cinnamon, and sugar. If using, mix in the coconut oil or butter until well combined. The mixture should look crumbly but slightly moist.
Spoon the filling mixture into the cavities of the prepared apples. Pack it lightly, but don’t overfill to prevent spilling during baking.
Place the filled apples upright in a baking pan or casserole dish. Choose a dish where the apples fit snugly but not too tightly. Add hot water to the bottom of the dish to create steam and keep the apples moist.
Bake for 40 to 50 minutes. To check doneness, insert a sharp knife into the side of an apple; it should slide in easily without resistance.
Remove from the oven and let the apples cool slightly. Serve warm, either as they are or with a dollop of yogurt or ice cream for an extra treat.