Peel the potatoes and chop them about the same size as the chicken if possible.
Put some coconut oil or ghee into a large pan.
Fry the onions until brown and soft.
Add 1/2 a teaspoon of whole cumin seeds(sabut zeera) and fry for few seconds only.
Add the chicken, potatoes and the ginger and garlic paste. Season, stir well and cover to cook. This should take about 30 minutes or until chicken is almost done. Keep stirring a few times in between.
When the chicken and potatoes are almost done, add the fresh tomatoes, the can chopped tomatoes, chilli, ground cumin, and chickpeas(chane).
Stir well to mix and let it cook for another 10 minutes or so. The tomatoes should be reduced and sticking to the bottom.
If you want a little saucy then add about 2 cans of water and simmer.