I knew a guy who used to boil a chicken, but you must save the stock also, or broth or how you say in English. Anyways, then let it simmer until about 1/2 volume remains, then add spices like curry and celery, then final touch also add 1 fresh grated apple, then thicken sauce with flour, then add chicken meat. Now I forgot important thing, broth must cool before reducing to half amount. When it is cool, remove the fat from broth. The fat does not taste good. Then proceed as I mentionend above.