Ambot Tik

Ingredients :

½ kg fish preferably skate, shark or catfish
10 dry red chillies
¼ tsp cumin seeds
4 peppercorns
¼ inch piece turmeric
4 flakes garlic
½ inch piece ginger
a small (marble size) tamarind
1 onion (sliced fine)
2 tbsp oil 

Preparation : 

Clean and wash the fish. Cut into desired pieces, apply salt and keep aside. In the meantime grind the above ingredients in a little water.

Fry the onion in oil till it turns brown. Add the masala and fry a bit. Add a cup of water, allow to boil and then add the fish pieces. Cook till tender on slow fire. Add salt and vinegar if necessary. 
Please note that shark ambot tik is said to be well acclaimed but smaller fish can also be used.