Place fish in a bowl. Heat coal over a flame until it glows. Push a beetle nut leaf (paan leaf) into the centre of the bowl of the fish. Using tongs, put the glowing coal onto the leaf. Heat 1 tbsp oil. Pour over the coal. Cover the bowl with foil. Set aside for ½ hour. Arrange fish on a grill pan. Brush with butter and grill until fish flakes easily. Flake fish with a fork. Cook butter, spring Onion and cream together for a minute. Add potatoes, parsley, nutmeg, fish and seasoning. Chill well. Mould mixtures into small patties. Coat with flour. Shallow fry in hot oil for about 3 minutes on each side. Drain and serve immediately.