In a large pot, skillet or dutch oven, add 2 tsp olive oil and heat over medium-high heat. Add chicken, season with salt, pepper, Italian seasoning and garlic powder. Cook about 5 minutes, until chicken is most of the way cooked through. Remove to a plate.
Add onion and garlic to the pot and cook about 2-3 minutes, until soft. Pour in sauce, then fill up empty jar or measuring cup with water (3 cups) and add to the pot. Bring to a boil, then reduce to a strong simmer.
Add chicken and pasta, stir, then cover and cook for 10-15 minutes until pasta is done to your liking. Stir in parmesan cheese and 1/4 cup of the mozzarella.
Sprinkle remaining mozzarella on top of pasta and cook another 2-3 minutes until cheese is melted and gooey.
Sprinkle with additional Italian seasoning, if desired and garnish with basil or parsley.