Preheat oven to 400 degrees. Cut the spaghetti squash length wise, and spoon out all the innards and seeds. Lightly mist with olive oil or cooking spray, and sprinkle with salt and pepper.

Place both halves cut side down on a baking sheet, and roast for 40 to 50 minutes, or until the flesh is very tender when poked with a fork. Allow squash to cool.

While squash is roasting, heat the oil in a large skillet over medium heat.

Add the onion and garlic and sauté until translucent, about 5 minutes. Add the turkey, and sauté until meat is no longer pink. Add the carrot and sauté until tender, about another 5 minutes.

Add the marinara sauce. Decrease the heat to medium-low and simmer gently for 15 minutes to allow the flavors to blend, stirring often. Season as desired with additional salt and pepper.

Using a fork, scrape out the strands from the inside of the spaghetti squash, and divide evenly into 4 servings. Top with bolognese sauce and serve immediately.