Marinate Hilsa/ Ilish Maach with 1 Tsp. Salt, 1 Tsp. Turmeric Powder and also 2 Tbsp. Mustard Oil.
Keep the fish marinated for 15 minutes
Remove the skin of the Pumpkin and cut Pumpkin into small cubes.
Take 2 green chilies and cut them into halves.
Heat a pan and add 6 Tbsp. Mustard oil to the pan.
Heat the oil till it changes color.
Now lightly fry fish chunks one by one.
Fry one side for 30-45 seconds.
Turn the fish and fry for another 30-45 seconds.
Strain from the pan once lightly fried on both sides.
Following the same process fry the remaining fishes.
Separate around 3 Tbsp. Oil from the Pan.*
Add 2 cups of water to the bowl having the marinade. This will be added while cooking the fish.
Temper remaining oil in the pan with 2 dried red Chillies,
Add 1 Tsp. Nigella Seed aka Kalojire as well.
Mix with a spatula and cook for 30 seconds on low flame till it emits the aroma of the spices.
Now add Pumpkin cubes and cook on low flame.
Add 1 Tsp. Turmeric Powder, 1 Tsp. Red Chili Powder as well.
Also, add ½ Tsp. Salt.
Mix again to incorporate spices and cook for 3 minutes on low flame.
Now add the Water mixed with marinade and cook on low flame for 10 minutes.
At this point add tamarind paste.
Mix in between and add Green Chillies.
After 10 minutes, the pumpkin will be properly cooked.
Add fried fishes one by one and cook for 5 minutes after adding the fishes.
Add 1 Tbsp. raw mustard oil to the Hilsa fish curry. This step is optional.
Switch the flame off and give a standing time of 5 minutes before serving.
Serve it hot with steamed rice!