Brown the ground beef and turkey sausage in a large pot over medium-high heat until browned. Drain excess grease if needed.
Add diced onion and bell peppers. Cook 4-5 minutes until softened. Stir in garlic and cook for 1 minute.
Add tomato paste and cook 2-3 minutes. Season with Nature's seasoning, Cajun seasoning, and Italian seasoning.
Sprinkle in flour, stir well, and cook 1-2 minutes to create the 'dirty' roux.
Slowly add beef broth while stirring. Let simmer until thickened.
Either add dry spaghetti directly to the pot (breaking in half if needed) and cover until tender, or boil spaghetti separately in salted water until al dente.
If using the separate pasta method, reserve ½-1 cup pasta water and drain noodles.
Add cooked spaghetti to the meat sauce and toss well.
Add a splash of pasta water to loosen and emulsify the sauce until silky.
Garnish with fresh chopped parsley and serve.
