Kerala fish curry

king fish-1/2 kg ( or any fish)
small onions-5
green chillies-3
kodumpuli-2
ginger -1 inch cut into lengthwise
garlic -3 cloves
grated coconut-1/2 cup
chilly pwd- 1tbsp
turmeric pwd-1/2 tsp
salt- as required
c'oconut oil-2tsp
curry leaves
To grind:
Grind coconut, chilli pwd, turmeric pwd,  small onions-3,garlic,  green chillies-2 into fine paste.
METHOD:
Soak kodumpuli in 1/2 cup f water for 15 min.
 In a kadai add the ground paste, 1 cup of water, kodumpuli along with that water, salt .
Let it boil for 3 minutes.Now add fish and let it cook  for 5 minutes or until fish is done.
Now in a kadai heat 2 tsp oil add mustard seeds,when it splutters add ginger pieces and remaining small onions(chopped), slit green chilli-1, curry leaves.
Pour this seasoning over the curry .
Mix gently so that the fish pieces don't break. Serve hot with plain rice.