Marinate the mutton with ginger garlic paste, spice powder and yogurt. Mix well and keep it aside for 4-5 hours.
In the meantime, fry the thin onion slices in 1 cup of hot oil until they become golden brown in color. Do not make dark in color and fry them in batches.
Heat 4-5 Tablespoons of oil in a pan. Saute the whole spices for few seconds.
Add the marinated mutton, fry on medium flame for 10 minutes.
Add salt as per your taste, mix well.
Now put the fried onion in a grinder, grind them to a coarse powder. You can do this with your hand also.
Then add the ground fried onion into the mutton, mix well and cook for 15 minutes on medium flame.
Add 2 cups of water, mix well, cover the pan and cook until the mutton becomes fully soft.
Lastly add garam masala powder, kewra water, chopped green chilies and coriander leaves.
Mix well and turn off the heat. Let it rest for 30 minutes then serve.