This is a traditional Bengali dish made with the very popular Rui fish. It is considered very special because it is so rich in flavor. It is served with pulao or flavored rice, like lemon rice or cinnamon rice.
Heat a pan with soybean oil and fry the fish pieces.
Transfer the fish pieces. Now add the ghee to the pan and heat again.
Add the onion slices and fry until slightly golden in color.
Add the bay leaves, cardamoms, cinnamon sticks and cloves. Also mix in the ginger, garlic, onion and postadana pastes. Pour in 1 cup of water and cook for 10 minutes until the water dries up slightly and the oil starts to simmer on top
Lay out the fish pieces all over. Cook for a bit while turning the sides of the fish pieces.
Now pour in the yoghurt and cook for another 20 minutes.
Sprinkle the sugar and stir
Finally sprinkle the green chilies, raisins and pistachio nuts.
Cook for another 10 minutes on low heat until the oil and ghee start to float on top and a thick gravy forms.