It seems a little odd that the seafood-loving residents of Spain and Portugal love salt cod so much. In fact, the closer to the water they live, the more salt cod they seem to eat. These people, who have access to the best fresh seafood in the world, on any given night you’ll find them cooking slabs of preserved salted fish. It stymied me until I married into a Portuguese family and started eating more salt cod. Then I realized that salted cured fish has about as much in common with fresh fish as cured ham does with a fresh pork chop. They're two completely different things. People who raise pigs like fresh pork and they like salted cured pork like ham. Why wouldn't the same be true for people who fish?
The salt curing and cooking—which, here, happens as a slow confit in olive oil—creates a cod fillet that’s almost creamy. It may seem counterintuitive but salt cod is one of the most luxurious fishes you can eat. That's the main reason Iberians spend hours—and I mean hours—soaking and cooking it. The salt cod in this jar, on the other hand, takes all of two seconds to prepare. Turn the lid, turn out the fish, feast.
"Move over, tuna. Succulent jarred codfish fillets preserved in olive oil from Spain’s Basque Country give new personality to scores of dishes."
Florence Fabricant, The New York Times