Skin chicken pieces, score with sharp knife. In non-metallic bowl,mix all ingredients. Marinate chicken in mixture overnight, turning to marinate evenly. Cook on brazier bbq so that flames have direct contact with chicken (ie not on a hot-plate), or in a vertical grill on maximum heat. The object here is to emulate the tandoor as much as possible in cooking with intense, dry heat. Serve with rice, naan, lettuce, onion rings, cucumber slices and lemon wedges. I personally add ground mint and ground very hot chilli powder the above marinade. I probably don't want to know what the original red coloured powder is in the tandoori powder I buy from Indian spice merchants, but it adds to the authenticity. I now mainly use a powder tandoori marinate from Keens. It is cheap, easy and authentic. Have fun.