Wash and clean the fish by adding little salt.
Clean and keep aside.
To prepare the coconut mix, coarsely blend ( just pulse it in mixer for 2 secs) or crush together grated coconut,shallots ,ginger,garlic and green chillies.
In a pot or vessel add fish pieces ,pot tamarind, ground coconut mix , turmeric powder,red chilli powder,salt, curry leaves, coconut oil and 2 cups of water.
Cover and cook on medium flame for 5 mins.
Open the lid and cook for another 15 to 20 mins or till all the water dries up.
Keep stirring in between but do not over mix.
Switch off the flame and keep it aside for sometime before serving.