Heat oil in a pan. Temper it with Nigella seeds/Kalo Jeera/Kalonji and Green Chilies.
Once it starts spluttering, place the fish pieces in it. Fry each side for 2-3 minutes of high heat till it turns golden.
Once done, add water, Salt and Turmeric Powder. Allow this to simmer for another minute or two.
Before serving top it with finely chopped Coriander leaves.
It is always advisable to marinate the fish with some salt and turmeric powder before cooking. This ensures that salt seeps in and seasons the fish properly.