Heat the oil in a large non-stick pan and add the cloves and cardamom. Once they start sizzling, add the onions and fry until golden brown. Add the chillies, ginger and garlic, and cook for 30 seconds.
In a bowl, mix together the curry powder, tomato paste, yoghurt, sugar and salt. Pour the mixture into the pan and cook, stirring frequently. Add the chicken livers and 60 ml of water, mix well and cook for 5 minutes. Remove the livers from the pan and set aside.
Add the nutmeg and tomatoes. Put the lid on and cook for another 15 minutes over medium heat. Return livers to tomato mixture, sprinkle with fresh coriander and serve with roti.