 It is also very common throughout the Mediterranean Basin and is found in Provence and Roussillon, France and in the coastal regions of Italy (where the most common variant using salt cod fillets is known as "filetto di baccalà") and Greece (where various fish like Mediterranean sand smelt, European anchovy, cod, common sole, greater amberjack and picarel are used).It was also eaten by the Romans in ancient Rome.It is made by coating the fish (usually a white fish) in flour and deep-frying it in olive oil, then sprinkling it with salt as the only seasoning.