Remove excess fat and chop the lamb into large chunks and place in a bowl

Add the garam masala and massage thoroughly into the meat

Add the garlic/ginger paste and massage again

Add the yoghurt and mix well. Then cover bowl with clingfilm and leave to marinade in fridge overnight

Remove lamb from fridge and allow to come to room temperature

Blend chopped tomatoes with tandoori masala and set aside

Heat the oil in a large heavy frying pan with the remaining temper ingredients

Slice half the onions and add to pan. Dice the remaining onion for later.

When sliced onions are soft, add the diced onion and cook the onions with a pinch of salt until golden, without burning.

Add garlic ginger paste and cook on high heat until water evaporated - about 30 secs

Add the cumin, coriander and chilli powder. If you cant get kashmiri chilli powder use 50% ordinary paprika mixed with normal chilli powder. Cook the spices for a minute on a high heat

Add the lamb to the pan and combine well with spices. Allow pan to return to temperature

Add the tomatoes and three tablespoons of yoghurt and return to temperature.

Cook over a medium heat for 20-30 minutes. The mixture should start to get thicker and drier, clinging to the meat.

Continue to brown the meat in the masala (spice mix) for 5 minutes.

Add enough hot water to cover and simmer until lamb is tender and sauce is thickened - anywhere between 30-60 minutes

Turn heat off and sprinkle over some garam masala. Then serve with rice/bread.