Pre-heat oven to 400° F.
Cut acorn squash lengthwise and scoop out seeds. Spray inside with olive oil spray. Season with salt and pepper and lay skin-side up on a foil lined baking sheet and roast in oven for 30-40 mins.
While squash is in the oven, brown sausage, set aside. In the same pan, sauté shredded carrots and onions in olive oil, until tender, about 5 mins.
Add apple, kale, sage, and water and sauté 5-10 mins, until apples are tender. Add nuts and maple syrup. Add sausage back in and salt and pepper to taste.
Remove squash from the oven and reduce oven temperature to 350° F. Place squash in a baking dish open side up.
Fill with the sausage mixture and return to oven.
Cook at 350° F until heated through (about 15-20 mins)