Marinate the fish pieces with a pinch of salt and turmeric powder for 10 minutes. Heat 3 tbsp. oil in a pan and fry the fish pieces on both the sides till light golden in colour. Keep aside.
Temper the same oil with panch phoron and allow it to splutter. Add the onion and saute till light brown.
Add the ginger-garlic paste, tomato paste, turmeric powder & red chilli powder mixed with some water. Saute till the oil separates.
Add 1/2 cup water, salt, fried fish pieces & slit green chilies. Simmer on low flame for 2-3 minutes or till the gravy is slightly reduced.
When done, switch off the flame and add the remaining mustard oil.
Garnish with coriander leaves and serve with hot steamed rice for a sumptuous meal.
