Beef-Stuffed Butternut Squash

1 butternut squash, cut in half and seeded;

1 lb. ground beef;

6 slices of bacon, cooked and crumbled;

8 oz. mushrooms, sliced;

2 carrots, diced;

3 red onions, sliced;

1 stalk celery, diced;

2 garlic cloves, minced;

½ tbsp. cinnamon;

Cooking fat;

Sea salt and freshly ground black pepper;