To begin making Bengali Style Hilsa Fish In Poppy Seeds & Yogurt Curry Recipe, first using a sharp knife, cut the hilsa into slices and clean.Marinate the fish pieces with salt in a mixing bowl and keep covered for about ten minutes. Also prepare the poppy seeds paste and mustard paste by using a blender/mixer, with about a tablespoon or two of water.In another mixing bowl, mix together red chilli powder, turmeric powder, yogurt, poppy paste, yellow mustard paste, curd, salt and water to make a paste.Meanwhile in a kadai, heat the mustard oil on a low flame. Once hot, add green chillies and nigella seeds for tempering, keep tossing for about a minute or till done.Place the hilsa fish on a cast iron frying/grilling pan on a medium-low heat, and pour the sauce mixture on top of fish to coat completely and cover the bottom of the pan.�Cover the pan and cook further for about 10 minutes.Check the salt and adjust to suit your taste, check if the fish is tender and cooked well. Once it is cooked well, switch off and serve.Serve�Bengali Style Hilsa Fish In Poppy Seeds & Yogurt Curry Recipe�along with�Steamed Rice,�Bengali Posto Porota Recipe,�Bengali Style Cholar Dal Recipe�and�Bengali Bhog Khichuri Recipe�for a wholesome lunch.