In a deep bottomed vessel, heat oil.
Add the chopped onions and fry until brown.
Add the green chilli, mint leaves, ginger and garlic and fry for a couple of minutes.
Add the tomato and fry until soft (if using chopped tomato) or fry until the oil oozes out on the sides (if using puréed tomato).
Add the red chilli powder, coriander powder and cumin powder and fry for a minute.
Add the chicken and cook under lid until the chicken is cooked and soft (add ¼ cup water if necessary).
Add coconut milk and cook for a couple of minutes.
Serve hot with steamed rice or roti.