Clean fish wash with salt and water and keep aside(use whole if you are using natholi or small fish)
In a blender add half of the shallot(five shallots),few garlic and turmeric powder,then grind it together .add the grated coconut and gently crush no need to grind well.
Take a clay pot then add cocum, curry leaves and green chili,then add cleaned fish, ginger and remaining garlic,then add grated coconut and salt.mix well with your hands.
add 1/4 cup water and cook covered for 15 minutes.gently stir in between.
once fish cooked well switch off the stove, then add 2 tbsp coconut oil.just swirl the pot then immediately cover with the lid and keep aside for 2-3 hours .Then enjoy with rice.