Fish (leftover) and rice (leftover) croquettes

Skin and debone the fish (if necessary) and flake it. Separately, lightly beat the egg.
Place the fish in a bowl and mix with the rice, beaten egg, flour, and grated lemon zest. Shape the mixture into small rolls, flatten them, coat in breadcrumbs, and fry in plenty of hot oil.
Drain the golden-brown croquettes and serve with a light side dish.