Saute carrots, onions, celery in corn oil, garlic, salt and pepper until tender Add chicken broth and bring to boil. Add tomatoes, Rotel, taco seasoning, and chicken Cut Tortillas into small pieces and add to broth mixture Let boil for 20 minutes or until tortillas are thoroughly incorporated into soup stirring occasionally to keep from sticking Reduce heat and add 8 oz. cheese. Simmer for additional 10 minutes. Add milk and simmer for additional 10 minutes If thicker soup is desired, add more diced tortillas and let incorporate into soup Garnish with shredded cheese and broken tortilla chips