Optional: A gravy can be made using a tablespoon of cornstarch or 2 tablespoons of flour to thicken 1 cup cooking liquid (or add water to equal 1 cup) and cook over high heat until thickened. You may add a small can of mushrooms to the gravy, if desired. To help prevent lumps, stir cornstarch into cold water until dissolved, or sprinkle flour over top of gravy using a fine mesh sieve.