Cook elbow macaroni according to package instructions, drained and set aside. In a large skillet over medium heat add olive oil, onions, garlic, and ground turkey. Cook until light brown, stirring to break up turkey. ( 3 - 5 ) minutes.
Add mushrooms, diced tomatoes, marinara sauce, Italian seasoning and let simmer ( 3 - 5 minutes). Then add bell peppers, salt and pepper to taste. Add cooked macaroni, shredded cheese and combine all ingredients well.
Sprinkle chopped parsley toss and serve with fresh grated Reggiano Parmesan cheese