Mix curd, Melam chilly powder, ginger garlic paste, saffron and salt. Wipe the chicken pieces and make deep cuts on the fleshy parts. Add this in the curd mixture. Mix well and keep aside for an hour. Heat oil add sliced onions and fry to pale golden colour. Add the chicken mixture. Stir well and bring to boil. Boil for 5 minutes, then reduce fire and cook till the chicken is tender. Add cashewnut powder, crushed cardamom, broken green chillies and simmer till oil separates. Add cream and cook on a slow flame for 5 minutes. Remove from fire. Serve garnished with coriander leaves and onion rings.