Stir in hot water, milk, uncooked pasta and sauce mix (from Hamburger Helper box), Italian seasoning and garlic powder. Heat to boiling, stirring occasionally.
Reduce heat; cover and simmer 5 minutes. Stir in tomato, bell pepper, zucchini and cheese. Cover and simmer for 5 minutes. Remove from heat; uncover and let stand for 5 minutes allowing sauce to thicken. Stir before serving.