Cut chicken into serving pieces skin all pieces.
Chop half of the onions coarsely, cut the remaining onions into halves and then crosswise into very thin slices. Put chopped onions, ginger and garlic into blender and blend into a fine paste, heat the oil in a large pan when hot put in the SLICED onions and fry until deep in colour, remove the onions and set aside.
Put in the blended paste and fry for 3-4 mins, now put in the coriander, cumin, turmeric and cayenne put in 1 tbsp of yoghurt and when it has been incorporated add another until all of it has been used. Put in the chicken and stir.
Pour in the water and toms. and salt, stir to mix and bring to a simmer, cover, turn heat to low and cook for 20 mins. sprinkle in the garam masala and the fried onions cook uncovered for 7-8 mins until sauce thickens serve with green coriander sprinkled on top.
