Preheat the oven to 400 degrees.
Cut your acorn squash in half. Scoop out the seeds and discard. Drizzle 1/2 tbsp olive oil, 1/4 tsp salt and pepper between the 2 halves.
Place squash on a lined baking sheet with the "flesh" side facing down.
Bake for 20-25 minutes until tender.
While the squash is cooking, heat 1/2 tbsp olive oil in a frying pan over medium heat.
Add onions and sauté for 2-3 minutes. Next add mushrooms and cook for 2-3 minutes. Finally add garlic and sauté for 1 minute until fragrant.
Lower heat to simmer then add apples and turkey. Cook for 3-4 minutes until begins to warm.
Add chicken stock, rosemary, salt and pepper to the pan. Give all ingredients a good stir and allow to simmer for 5-6 minutes.
When squash is cooked remove from oven and allow to cool. If squash is cool enough to touch, scoop out the middle of the squash and place onto a cutting board.
Roughly chop your squash so that it is in smaller pieces. Add 1/4-1/2 cup worth of squash into frying pan and stir everything together.
Finally divide your "stuffing" into the 2 hollowed out squash halves and add back into oven.
Bake for 5 minutes. Heat up your gravy.
Remove from oven & allow to cool. Drizzle gravy on top, serve & enjoy!