In a large skillet, cook beef, celery, green pepper and onion over medium heat until meat is no longer pink and vegetables are tender; drain.
Set aside topping packet from the dinner mix for another use. Stir the contents of dinner mix seasoning packet, chili powder and water into beef mixture. Bring to a boil. Stir in noodles from dinner mix. Reduce heat; cover and simmer for 12-15 minutes or until noodles are tender.
Stir in the cheese, tomatoes and olives; heat through. Serve with sour cream if desired.
Editor's Note:This recipe was tested with Hamburger Helper dinner mix.