Hilsa Fish Gravy Curry

Ingredients

• 1.5 pounds Hilsa fish, cleaned, head and tail removed, cut into 3/4-inch thick slices (About 4-6 slices depending on size of fish)
• 2 tablespoons Salt for washing fish (For cleaning the fish)
• 2 ounces Mustard oil (About 1/4 cup or 4 tablespoons)
• 2 cups Water
• 4 teaspoons Onions, ground to paste (About 1 medium onion)
• 1 teaspoon Ground turmeric
• 1 teaspoon Ground red chilies or chili powder (Adjust to taste)
• 0.25 teaspoon Garlic, ground to paste (About 1 clove)
• 1 tablespoon Tamarind pulp or amchoor (dried mango powder) (For sourness; use tamarind paste or 1 teaspoon amchoor)
• 1 teaspoon Salt (To taste)

Instructions

1. 1Remove the head and tail from the hilsa fish. Cut the fish into slices slightly more than half an inch thick (about 3/4 inch). Wash the fish slices in several changes of cold water with salt, rubbing thoroughly to remove all slime and impurities. Rinse well and pat dry with paper towels.
2. 2Grind the onions to a paste using a mortar and pestle or food processor. Grind the garlic to a paste. Measure out the ground turmeric and ground chilies. Keep all spices ready.
3. 3Heat the mustard oil in a wide, heavy-bottomed pan or kadhai over medium-high heat until it begins to smoke lightly. This removes the pungency of the mustard oil. Reduce heat to medium.
4. 4Add the ground onion paste to the hot oil and fry, stirring constantly, for 3-4 minutes until the raw smell disappears and the onions turn light golden. Add the ground turmeric, ground chilies, and garlic paste. Fry for another 2 minutes, stirring continuously to prevent burning.
5. 5Add the 2 cups of water to the pan, stirring well to combine with the spice mixture. Add salt to taste. Bring the mixture to a boil over medium-high heat, then reduce heat to maintain a gentle simmer.
6. 6Add the tamarind pulp or amchoor to the gravy and stir well to dissolve. If using tamarind paste, ensure it is well incorporated. Simmer for 2 minutes to allow the sour flavor to infuse into the gravy.
7. 7Gently slide the cleaned fish slices into the simmering gravy, arranging them in a single layer if possible. Spoon some gravy over the fish. Cover the pan and let the fish cook undisturbed for 8-10 minutes over medium-low heat. Do not stir, as hilsa fish is delicate and will break. You may gently shake the pan occasionally.
8. 8Check if the fish is cooked through by gently inserting a fork into the thickest part - it should flake easily. If needed, cook for another 2-3 minutes. Once done, remove from heat. Let rest for 2 minutes, then serve hot with steamed rice.