Pre-heat oven to 375 degrees.
Cut spaghetti squash in half lengthwise, scoop out the seeds, and rub cut sides with olive oil if desired. Season with Flavor God garlic lover's seasoning if desired. Place on a baking sheet, cut side up, and bake for 40-45 minutes or until flesh can be easily scraped apart with a fork.
Add turkey, sausage, egg whites, and breadcrumbs to a large bowl and mix with your hands to combine. Form mixture into approx. 1 1/2" meatballs and set aside.
Heat an oven-safe skillet over medium-high heat. Add olive oil and sauce mirepoix, garlic, and sweet pepper rings until fragrant and tender.
Add crushed tomatoes, tomato paste, Flavor God seasoning, and basil, then mix. Remove from heat and drop meatballs into the sauce.
Bake meatballs for 20-25 minutes or until cooked through. Serve on top of spaghetti squash.