Rub the fish pieces with little salt and turmeric powder. Heat oil in a pan and shallow fry the pieces.
Heat oil again and shallow fry the lentil dumplings. Remove from the pan and keep aside.
Also, shallow fry the potato pieces adding little salt and turmeric powder. Sprinkle some water and cover the lid for atleast 3-5 minutes. Make sure the potato pieces become little soft. Once it’s done, remove from the pan and keep aside.
In the same pan heat some more oil and add nigella seeds and dried red chillies. Stir for 30 seconds.
Now, add ginger-garlic paste, cumin powder, coriander powder and turmeric powder. Stir for another 30 second.
Add the chopped tomato pieces and stir until the pieces become soft.
Now, add potato and fried lentil dumplings and add required warm water for gravy. Add required salt and mix well. Cover the lid and bring it to boil.
Now, slowly add the fish pieces in the gravy and cover the lid again. Lower the flame and cook for 10-15 minutes or until the fish is well cooked.
Turn off the flame and garnish with chopped coriander leaves.
Your Bori diye Macher Jhol is ready to be served now.