Rinse chicken breasts and remove skin. In a large pot, cook chicken in about 3-4 cups of water. Boil until very tender.
While the chicken is cooking, spray tortillas with non-stick cooking spray and crisp each side in a pan or griddle.
Once the chicken is done, remove chicken to cool, then pull or cube cooked chicken. To the chicken broth add the cream of chicken soup, uncooked rice, milk, onion, and green chiles. Bring to a boil. Add chicken back into broth.
Spray a 13X9 pan with non-stick cooking spray. Place a layer of 6 tortillas, then chicken mixture and cheese. Repeat. (If the chicken mixture seems to soupy, sprinkle a little extra uncooked rice).
Bake at 350° for 25 minutes