Heat the vegetable oil in a large pan and toss in the cardamom pods. After a few seconds they will begin to sizzle and give off a lovely nutty whiff. As soon as this happens stir in the shredded ginger and chopped garlic, followed by the diced onions and curry leaves. Add a pinch of salt, this helps to speed up the browning of the onions.
Fry the onions over a medium heat until golden. Sprinkle in the turmeric, chilli powder, ground coriander and half of the ground cardamom. Stir and fry for a further minute before adding the water along with the chopped tomatoes and green chillies. Cook down until the sauce has thickened slightly.
Tip the chicken pieces into the pan, add a dash of water and sprinkle in the remaining ground cardamom.
Simmer the chicken curry for 20-30 minutes until the chicken is tender and the sauce has thickened.
Season to taste with salt and pepper. Serve garnished with a little more ground cardamom and scattered with chopped coriander and a few grinds of black pepper.