Soak the gambogee (kudam puli) in warm salted water and set aside. wash and clean the fish pieces well and set aside.

Heat the coconut oil in a vessel (preferably an earthen pot) and add the mustard seeds to it.

When the mustard seeds splutter, add the fenugreek seeds and let them turn a light brown.

Add the shallots, green chilly, ginger and half the curry leaves to the oil and sautee well.

When the shallots turn a light golden colour, add the turmeric, red chilly powder and coriander powder and saute well till the spices lose their raw smell.

Add the water used to soak the gambogee and mix well. bring the water to a boil.

When the water is heated through and just starts to boil, add the thin coconut milk and immediately reduce the heat to low. (its important to reduce the heat, otherwise the coconut milk will split)

Mix thoroughly and when the gravy is just heated through add the cleaned fish pieces, salt and the reserved gambogee. do not stir the fish, just swirl the vessel to coat the pieces in the gravy.

Cook the fish covered on a gentle heat for about 15 minutes, till the pieces turn opaque.

Add the thick coconut milk and remaining curry leaves, and swirl to mix. check for seasoning and add salt if required.

Once you add the thick coconut milk the curry shouldn't be kept on the heat too long. just warm the gravy through and take it off the heat.

Serve with white rice.