Roast the whole spices – Cumin seeds, Peppercorns, Cloves, Cinnamon and Khus Khus together in a dry pan and leave aside to cool
Grind to a powder once cooled
In a food processor add the Vinegar and roughly chop the chillies, garlic and ginger and blend
Add 1/2 the coriander, the spices a tsp of Turmeric and some water to help it blend
Add the second half of the coriander, 1- 2 tsps of salt and the soaked Tamarind(be sure to remove any seeds)
Pour the mixture over the Chicken and leave to marinate for a few hours and preferably overnight
Shallow fry on all sides and bake in the oven for 30 mins if required