Remove bones and skin from the fish, then flake. Boil the potato, mash and add to the fish. Finely mince the onion, ginger and chillis and add to the fish along with the breadcrumbs, egg and salt. Mix well and mould into walnut-sized balls. Fry the fish balls in oil till golden brown. Drain and set aside. Now make the curry. Slice the onion, mince ginger and chillis finely. Heat some oil in a saucepan and fry the cloves, cardamon and cinnamon for two minutes. Add the onion and fry till golden. Add the ginger and chillis, fry for a further two minutes and add the rest of the spices. Fry well for seven minutes then add sugar, lemon juice, salt, coconut and water. Bring to the boil and simmer very gently for 30 minutes. Add the fish balls, cook for 10 minutes and serve. Serve with plain boiled rice.
Note: Preparation time 15 minutes, Cooking time 45 minutes, To serve 4