Sometimes after roasting chicken you're left with a sauce in the roasting pan that you can use to make a gravy with. Otherwise, you can use it as a stock to make a soup. Add some chopped potatoes, a carrot, parsley, cream, pepper and maybe a touch of tomato. All the other seasoning from your chicken roast will be in the stock so you won't even have to add salt. Boil it for a few minutes and serve with fresh bread.
