
Made with AI
Rinse the hilsa steaks gently and pat them dry. Rub them with 4 g ground turmeric, 4 g salt, and 15 ml lemon juice. Set aside for 15 minutes.
Soak the yellow mustard seeds in about 60 ml of the measured water for 20 minutes. Drain, then blend them with the onion, half of the green chilies, and enough additional measured water to make a smooth paste.
Slit the remaining green chilies lengthwise and set them aside.
Heat the mustard oil in a wide pan over medium-high heat until it just begins to smoke. Reduce the heat to medium.
Add the nigella seeds and let them sizzle for about 20 seconds.
Add the mustard-onion paste, the remaining 4 g ground turmeric, and the remaining 4 g salt. Cook for 4–5 minutes, stirring frequently, until aromatic and slightly thickened. Do not brown the mustard paste.
Pour in the remaining water gradually and stir until the gravy is smooth. Add the slit green chilies and bring the gravy to a gentle simmer.
Carefully place the marinated hilsa steaks in the gravy in a single layer. Cover and cook over low heat for 6 minutes.
Turn the steaks very gently, cover again, and cook for another 5–6 minutes, or until the fish is cooked through and the gravy has lightly thickened.
Remove the pan from the heat and drizzle in the remaining 15 ml lemon juice. Rest the curry, covered, for 5 minutes before serving with steamed rice.