Clean 500 grams of fish and cut it into pieces. Marinate the fish with a pinch of turmeric and salt for about 15 minutes.
Grind 1 cup of grated coconut, 5 dried red chillies, 1 tablespoon of coriander seeds, 1/2 teaspoon of turmeric powder, and 1 teaspoon of tamarind paste into a smooth paste using a little water.
Heat 2 tablespoons of oil in a pan. Add 1 finely chopped onion and sauté until it turns golden brown.
Add the ground paste to the pan and sauté for a few minutes.
Add 2 cups of water, salt to taste, and bring the mixture to a boil.
Add the marinated fish pieces to the pan and cook on a medium flame for about 10-15 minutes or until the fish is cooked.
Garnish with fresh coriander leaves and serve hot with rice.