Style Fish Soup with Cassava

My Grand mother and my mother used to make Gangan (Belitung style fish soup) for our family. We lived near seaside when I was a kid, no wonder I love seafood. Guess, what is the best part I love in this soup?. Cassava!

ingredients:
500 g mackerel, discard inside, wash and cut into pieces
500 g cassava, cut into pieces
1 l water
2 bay leaves/daun salam
1 tablespoon tamarind paste + 100 ml hot water, sifted
1 teaspoon sugar, salt to taste

spices to grind: 3 shallots, 3 candlenuts, 2 cloves garlic, 2 cm ginger, 2 cm galangal, 3 cm turmeric, 4 bird´s eye chillies, 1 tsp shrimp paste/terasi/belacan, 2 cm lemon grass (take the white part only)

directions:
Boil water in a saucepan. Add spices, tamarind juice, bay leaves and cassava. Lower the heat, add mackerel, salt and sugar to taste. Simmer until the fish and cassava quite tender. Be careful not to overcook or they will disintegrate.