Marinate chicken with ginger garlic paste,kashmiri mirch powder,black peooer powder,turmeric powder,coriander powder,sauf powder/fennel seeds powder,salt and vinegar.Keep aside for 30 mins.Heat 1/2 cup oil in a pan.Add sliced onion and curry leaves and fry till transparent.Add marinated chicken and mix well.Cover and cook in a low flame.Add little water and cook for 7 - 8 mins.Serve hot with chapatis.