Marinate mutton with ginger garlic paste and chili powder, mix well, keep it aside and cool for few hours in fridge.
Heat ½ cup oil in a pressure cooker, add the mutton, grind onion, coriander leaves and green chilies, add to the pressure cooker.
Fry for 10 mins, pour 1 cup water, pressure cook for 20 mins, open the cooker, cool and simmer till the gravy is reduced and oil comes on top, add vinegar, simmer for a few mins.
FOR BAGHAR
Put ¼ cup oil in a fry pan, add dried red chilies, curry leaves, fry for 10 secs, pour it on mutton, simmer for 10 mins, serve with roti.