Madras Lamb Curry

2 T peanut oil
1.5 kg diced lamb
2 onions, chopped coarsely
2 cloves garlic
1 T cumin
2 T ground coriander
2 t garam masala
1 t chilli powder
1 cinnamon stick
5 tomatoes, chopped coarsely
3 C beef stock
400ml coconut cream

Heat half of oil, cook lamb in batches, remove. Heat remaining oil and cook onion, garlic. Add spices 2 mins or until fragrant. Return lamb with tomato and stock. Bring to boil, simmer uncovered 1 ½ hours. Add coconut cream, simmer further 10 mins or until just thickened.