Spiced roast lamb

1. stab the lamb all over with a sharp knife 2. mix all the ingredients togehter (other than the lamb) 3. smeer yoghurt mixture all over lamb ensuring it goes into cut marks 4. put in fridge to marinate for at least two hours 5. preheat oven to 180c/350f/gas 4 6. put lamb in roasting tin and cover loosely (but airtight) with foil to ensure juices stay in 7. cook for approx two hours until lamb is cooked to degree you prefer 8. remove foil and cook for 10 minutes to allow 9. rest before carving 10. use juices for base for gravy.