Mutton pieces are marinated in yogurt then slow cooked until tender.
There a tons of recipe for Korma. One of them uses ground almond, cashew or grated coconut like this and this . You can use chicken, beef or lamb for cooking the recipe. . .
This Mutton Korma uses pounded fried onion and to be marinated for at least an hour. The marination not only gives a tasty flavor but also help to tenderize the meat.
Another difference was, this Mutton Korma does not involve sauteing the spices in ghee as you normally do, The spices, yogurt and ghee are added together with mutton.
Pounded cinnamon, clove, peppercorn and cardamom are also used