Soak cocum in 3 tbsp water for 10 minutes.
Mix the powders (chili,coriander & turmeric) together with coconut oil/water & make a paste.
Heat oil in a meenchatti (earthen ware) or a pan & splutter mustard & fenugreek. Add crushed ginger garlic paste & stir for 3,4 minutes. Add small onion & curry leaves & saute till it becomes soft.
Add the masala paste, salt & fry till oil starts appearing. Add cocum along with the water & fish pieces. Combine well.
Make sure that fish pieces do not get broken in the process, it will be safer to rotate the pan to ensure that fish & masala is mixed well.
Add required amount of water & cook till the fish is done & gravy becomes thick, it will take around 20 -25 minutes on low flame.
Serve with rice or kappa (tapioca)
It tastes better the next day.