Add half and half, marinara sauce, cooked macaroni and ½ cup of the Parmesan cheese. Stir and cook for 5 minutes.
In a large skillet heat the olive oil and add chicken. Cook chicken for about 5 to 10 minutes until slightly browned, and cooked through. Add chopped onion and bell pepper and cook for another 3 minutes or until onion is tender. Sean with salt and pepper. Add zucchini and stir.