Boil chicken breasts 20-30 min till cooked through. Chop and set aside. Mix tomato sauce, chiles, nacho soup and cream of chicken soup. Divide in half. Combine half of sauce mix with shredded cheese and chicken.
Fill tortillas with mixture and place in a 9x13 pan. Cover with remaining sauce.
Cook at 350 degrees F for 30-35 minutes. Serve with sour cream.