Marinate the fish pieces with a pinch of salt & turmeric powder for 10 minutes.
Heat oil in a pan and fry the fish till golden in colour. Drain and keep aside.
Temper the same oil with fenugreek seeds. Saute for a few seconds and then add the onion. Stir fry till light brown.
Add the ginger-garlic paste, turmeric powder and green chilies. Saute for a minute.
Then add the tomato puree and salt. Cover and simmer for a minute more.
Add 1 cup water and bring it to a boil. Add the fried fish and simmer, covered on a medium flame for 3-4 minutes.
When done, add the coriander leaves.
And lime juice. Switch off the flame and transfer to a serving dish.
Serve this Assamese delicacy with hot steamed rice.
