Cook chicken. Drizzle1-2 Tablespoons olive oil in a large skillet or dutch oven pot. Heat over medium high heat. Then add 1 1/2 pounds diced chicken in an even layer. Sprinkle the salt, pepper and Italian seasoning over top. After 3-4 minutes, flip the chicken and cook an additional 2 minutes or until cooked through. Remove chicken and set on a plate. Cover and set aside.
Saute onion and garlic. Addmore oil to the pot if needed and then add in 1 cup onion. Cook about 2 minutes and then add in 2-4 Tablespoons garlic. Cook an additional 1-2 minutes or until onions are translucent.
Pour in sauce and pasta. Add 32 ounces marinara and 3 cups water into the pot. Bring to a light boil and then reduce the heat to medium. Add in 10 ounces pasta. Stir and then cover with a lid and cook for about 12 minutes, or until the pasta is cooked through. Stir once or twice.
Assemble. Add the chicken back into the pot. Stir in 1/4 cup parmesan cheese and 1/3 cup of the mozzarella cheese. Salt and pepper to taste.
Melt remaining mozzarella. Finally, add the remainder of the mozzarella cheese on top. Place the lid on and cook an additional 2 minutes over low, or until the cheese is melted. You could also put under the broiler for a minute if desired. Sprinkle with fresh parsley or basil, if desired. Serve while warm.
Notes
Storage: Store leftovers in a covered container for up to 3 days.