First make the spice blend. Lightly roast the spices in a dry pan being careful not to brown or burn. Add to a spice blender or pestle and mortar and grind to a fine powder.
Chop the onions and add to a medium pan with a little oil and fry gently for about ten minutes. Add the ginger, garlic and chilli and fry for a couple more minutes. Now add the chicken and the spice blend and fry over a higher heat for a couple more minutes. Add the tomatoes and the rest of the spices and bring to a high heat. Add the coconut mik carefully by just using the cream from the can. The sauce should now cover the meat, if you need more liquid add some of the water from the coconut milk can.
Cook on a low heat until the chicken is tender, if the bone is in the thigh it will take about an hour, without the bone a little less. You can;t really overcook this to be honest. If you need to reduce the sauce then take the lid off towards the end.
Serve with basmati rice. To cook the rice add 1 cup of rice to a pan, add 1.5 cups of water to the pan and bring to the boil with the lid off. Stir once, turn down to a very low heat and put a lid on. Cook like this until the water has been absorbed, if the rice if still a little crunchy then just turn off the heat and leave it to steam. The whole process takes about 20 mins