Preheat oven to 350 degrees. Mix chicken, cooked spaghetti, cheese, cream of mushroom soup, evaporated milk, chicken broth and olives, if using. Place in a 9-by-13-inch casserole dish. Bake 45 minutes, or until hot and bubbly.
To package for freezing: Put mixed ingredients from mixing bowl into freezer bag and try to remove most of the trapped air. Seal and flatten to freeze. Thaw in refrigerator overnight. Spread in casserole dish and bake according to recipe directions.
This recipe can be multiplied, but you may need to add more chicken broth. Some recipes seem to need a little more liquid when they are frozen, thawed and cooked.