Cook and debone chicken. In frying pan, cook 2 to 3 tablespoons cooking oil, 1 medium onion, chopped, 1/4 cup chopped bell pepper or green chilies, if preferred until onion is clear. Add 2 heaping tablespoons flour, 1 1/2 cups chicken broth, 1 can cream of chicken soup, 1 can cream of mushroom soup, 1 cup milk. Stir until smooth; add chicken.
Alternate in greased casserole a layer of corn tortillas, chicken mixture and grated cheese. Continue until ingredients are used. Will make a 9x13 inch casserole or two smaller. Freeze, if desired.
1 can chopped green chilies may be added, if desired, before layering in casseroles.