Firstly, take the fish pieces in a pan, add turmeric powder, salt, chilli powder, add less than 1/2 cup of water. Cover and cook for 2 minutes. Flip the fish pieces and cook for another 2 minutes.
Check the doneness of the fish. If you still see water, either strain the stew, preserve it, and use it in fish curry.
Dethrone the fish if necessary and crumble it by hand.
Pour little oil into a pan and heat it. Add Fennel seeds and then curry leaves for seasoning. With this, add the chopped onions and saute well until they become translucent.
Once onions are translucent, add the fish crumbles into it. Check for salt and spiciness and adjust if required by adding more salt, chili powder.
Add grated coconut with this mixture.
Switch off the flame and add the beaten egg into the fish-onion mixture.
Before making the cutlets, Take a boll of the mixture and pat it gently. Ensure it is tightly packed, else it comes apart when placed in the oil.
Make some patties and leave them for a while.
Heat oil in a hot Tawa or nonstick pan. Lay the patties over the heated oil.
Flip when it starts browning. Fry both the sides well.
We usually move the cooked patties to the edges of the Tawa to drain the excess oil. Fry remaining patties similarly.