Wash Kudampuli (Tamarind) and soak in hot water for about 15min, so as to make the extract easy and fully.
Blend 2tsp of chilli powder in a mixie with little water. This adds more flavour than adding chilli powder directly.
Slice Ginger, Chilli and small onions.
In coconut oil, add fenugreek seeds, roast a while then add ginger, garlic and small onions. Roast for about 5min.
Add 1tsp of Coriander powder and saute for 2-3min.
Add the chilli powder (that is blended in the mixie) and saute for a while till oil separates. Make sure the flame is medium or low or else it will burn out.
Next add Kudampuli (tamarind) along with the soaked water.
Add ½tsp of turmeric powder, pinch of fenugreek powder, curry leaves and salt and let it boil.
When it starts boiling add the fish pieces and keep the flame to low or medium. Cover and cook till the fish is done. Make sure not to mix it deeply with spatula else the fish pieces will break.
Adjust salt accordingly. This curry tastes good with little extra salt and sourness from the tamarind. So dont compromise on that. Also if you need thick gravy, add coconut milk and switch off immediately before letting it boil. or else dry roast coconut, grind it and then add to the gravy for a more thicker and tastier version.