In a large skillet coated with cooking spray, cook beef and peppers over medium heat 6-8 minutes or until beef is no longer pink and vegetables are tender; crumble beef; drain. Stir in salsa, corn and water; bring to a boil., Stir in tortilla strips. Reduce heat; simmer, covered, 10-15 minutes or until tortillas are softened. Sprinkle with cheese; cook, covered, 2-3 minutes longer or until cheese is melted. Serve with sour cream. Freeze option: Freeze cooled meat mixture in freezer containers. To use, partially thaw in refrigerator overnight. Heat through in a saucepan, stirring occasionally; add water if necessary. Serve with sour cream.