Use the drippings from the roasting pan, skim off all but 4 tablespoons of the fat in the pan. Place the pan over high heat. Add the turkey or chicken stock and bring to a boil, scraping the bottom to loosen browned bits. Reduce the heat. Mix the flour and water together and whisk into the gravy. Blend well; add the giblets if desired, and simmer 5 minutes. Season with salt and pepper, to taste.;