RUI MACHER GANGA - JOMUNA 
This delicious dish is mainly for special occasions. It is a combination of two favorite ways of cooking fish in Bengal - the literally sharp-as-mustard jhal and the more homely awmbol (a sweet-sour gravy of tamarind). Each piece of fish tastes tangy on one side and spicy on the other, and the union of the rich brown and dotted golden gravies gives the dish its poetic name. In some families, this recipe goes by the name of Horo-Gouri,for the contrary colors of the gravies allude to another celestial pairing, of the golden goddess and the dark god.
Ingredients
Rohu pieces or Fish salt
: 750 gm
Haldi(turmeric)
: To taste
Imli(tamarind)
: Dried
Lump
: 2 inch
Sour imli paste
: 1/2 cup
Mustard seeds
: 2 tbsp
Sharp mustard oil
: 1/2 cup
Green chilllies
: 2
Sugar
: To taste
Method
- Rub the fish lightly with salt and haldi; Keep to one side.
- If dried imli is used, soak in ½ cup water to loosen it first. Meanwhile, preheat oven to 180°C (350°F).
- Mix mustard paste with ¼ tsp haldi, ½ tsp salt, 1 cup mustard oil and the Green chillies. Set aside.
- Heat oil in a pan and add the cumin seeds,bay leaves,once they crackle,add the chopped onion.
- If imli is soaked, rub to remove seeds, husk, and fibres.Strain. Add 1 tsp haldi, ½ tsp salt, sugar, 1 cup mustard oil and the green chilies. Set aside.
- Lay the fish pieces in a shallow glass or ceramic dish. Carefully add the imli paste on one side and the mustard paste on the other. Gently shake the bowl so that both thick pastes come together along the center line but do not combine. Tent with foil and bake for 20-25 minutes (depending on size of pieces; a whole fish may need 30 minutes).
- Serve with plain rice, but present the dish as it is to make an impression.