Refrigerated Leftovers. Cooked chicken, chicken broth, fried chicken, chicken soup, chicken casseroles and cooked chicken leftovers from a restaurant or convenience store can be safely refrigerated for three to four days, according to the United States Department of Agriculture.efrigerated Leftovers. Cooked chicken, chicken broth, fried chicken, chicken soup, chicken casseroles and cooked chicken leftovers from a restaurant or convenience store can be safely refrigerated for three to four days, according to the United States Department of Agriculture.