Ingredients:

For the marinade:
1 tsp ground turmeric
1 tsp ground fennel seeds
1 tsp garam masala
1 tbsp white poppy seeds
salt, to taste
3 large garlic cloves
1 tbsp peeled and roughly chopped fresh ginger
1 medium onion, chopped
2 medium tomatoes, chopped
800 g / 1 lb 12 oz lamb, cut into small cubes with the bone left in

For the curry:
3 tbsp vegetable oil
¾ tsp nigella seeds (available from Asian grocers)
1 tsp cumin seeds
500 ml / 17 fl oz water
5-8 fat, short green chillies, slit through the middle, seeds removed, but otherwise left intact
2-3 tsp fresh tamarind paste
2 handfuls fresh coriander, leaves and stalks, chopped

Directions:

For the marinade, place all the ingredients, excluding the lamb, for the marinade into a food processor and blend until smooth.

Transfer the marinade to a bowl, add the lamb and leave to marinate for several hours, or overnight, if possible.

For the curry, heat two tablespoons of the oil in a large pan, add the nigella and cumin seeds and stir fry for about 30 seconds, or until the cumin begins to brown.

Add the marinated lamb and cook over a medium heat, stirring frequently, for about 12-14 minutes. Taste to ensure the spices have been cooked - it should have no harsh elements.

Add the water and bring to the boil. Then lower the heat, cover and simmer for 35-40 minutes, or until the lamb is tender. Check on the pot regularly, stirring occasionally and adding more water if it gets too dry.

Halfway through cooking the lamb, heat the remaining oil in a small pan and gently fry the chillies for two minutes, stirring often. Pour into the curry.

Once the lamb is cooked, uncover and stir in the tamarind paste. Taste and adjust the seasoning, add a little extra water if necessary, and stir in the coriander. Serve with naan or rice.