Soak Kashmiri red chillies in hot water for 15 mins. Deseed the mild hot red chillies and soak in hot water.
Peel and clean the ginger and garlic and chop them randomly. Clean and chop tomatoes.
In a blender jar add soaked chillies, ginger, garlic and coriander seeds and make a fine paste.
Wash the chicken pieces properly and squeeze out extra water.
In a mixing bowl add chicken pieces, above paste, yoghurt, salt and gram Marsala powder and mix properly so that chicken will have a proper coating. Let it marinate for 2 hours.
Heat oil in a thick buttom pan and add whole garam masala to the oil. Then add sliced onion and saute till golden brown. Then add marinated chicken and tomatoes to it and saute till dry.
Now add hot water to the chicken and cover it. Cook the dish up to chicken is soft and oil separates. Stir occasionally in between.
Garnish the dish with coriander leaves and a great combo for roti