1 tablespoon olive oil
1 acorn squash, halved and seeded
1 apple, diced
2 tablespoons diced celery
2 tablespoons water
2 teaspoons minced onion
2 teaspoons butter, cubed
1 teaspoon maple syrup
1 pinch ground cinnamon, or to taste
Preheat oven to 400 degrees F (200 degrees C).
Lightly grease a baking sheet with olive oil.
Place squash, cut-side down, on baking sheet.
Combine apple, celery, water, onion, and butter in a small baking dish; cover with aluminum foil.
Bake squash and apple mixture in the preheated oven until squash and apple are tender, about 45 minutes. Fill squash halves with apple mixture; drizzle with maple syrup and sprinkle with cinnamon.
Optional: Add some cranberries or raisins to the mix for a little added color and flavor.