This is not a gratuitous comparison. As Harold McGee writes in his encyclopedic work of food science, On Food and Cooking:

The best of these [salted fish] are the piscatory equivalent of salt-cured hams.

In both, salt buys time for transformation: it preserves them long and gently enough for enzymes of both fish and harmless salt-tolerant bacteria to break down flavorless proteins and fats into savory fragments, which then react further to create flavors of great complexity.

Amen.

This flavor alchemy explains why salt cod continues to be a cherished comfort food, even as dwindling catches have transformed it from a cheap staple into a pricey delicacy. Expensive comfort food may be a paradox, but thanks to overfishing or ecological change or whatever else is on the list of possible causes for the recent collapse of the Atlantic cod fishery, it is a fact of life.

Another salt cod paradox is that devotion to this homey and once humble food inevitably leads to faraway places and exotic cuisines.

Growing up in New England, we ate salt cod exclusively in the form of fish cakes. My mother made them for dinner, although traditionally they served as part of a working-class breakfast. I still make them, although sometimes, out of thrift, I substitute leftover cooked fish (bluefish and mackerel are good) or smoked fish for some or all of the salt cod.

During a college semester in Los Angeles I was introduced to chiles rellenos and enchiladas, but also found a life-changing Mexican salt cod casserole that Aztec-ed up the Iberian classic Bacalao a la Vizcaina with tomatillos and dried chilies. My mother-in-law taught me a spicy and vinegary salt cod dish from her Virgin Islands childhood called pickled salt fish (pronounced more like "sow fish").

Most Americans associate salt cod with Italians, but to true devotees, southern Europe from Lisbon to Istanbul is a magical mystery tour, in which each nation, region and city cooks the dish in its own way. The Portuguese are in a class by themselves as salt cod lovers. Great fishermen, they not only introduced salt cod to most of Europe, but also proudly claim to have more than a thousand distinct recipes for bacalhau — and not a single recipe for fresh cod.

New England Salt Cod Cakes

These are wonderful when made entirely with salt cod, but out of thrift, or sometimes just for the sake of variety, you can substitute almost any white-fleshed leftover cooked fish, or even smoked fish, for some or all of the salt cod.

New England Salt Cod Cakes. Photo: Tom Gilbert/NPR

Makes 4 servings

1 pound desalted salt cod

1 or 2 bay leaves

4 medium-size starchy potatoes, boiled and mashed or riced

1 medium Spanish onion, grated

2 eggs, lightly beaten

2 teaspoons finely chopped parsley

1 generous pinch ground black pepper

1 small pinch grated nutmeg

1/2 cup unseasoned breadcrumbs, or more as needed to bind the mixture

For dredging, 2 cups breadcrumbs, panko or flour

2 to 3 tablespoons of bacon fat or butter, or more as needed for frying

1 lemon, cut into wedges, or 1/2 cup tartar or hot sauce

Salt

Poach the desalted cod and bay leaf for 2 to 3 minutes in simmering water. Drain and flake cod; discard the bay leaf.

In a large bowl, mix potatoes, onion, eggs, parsley, black pepper, nutmeg and breadcrumbs.

Add flaked cod to bowl; mix all ingredients roughly by hand. The consistency should be moist but not so moist that you cannot form cakes about the size of a small hamburger that barely hold together.

Form cakes and place them on a wax paper-lined cookie sheet. Cover with wax paper, then cover with tin foil and refrigerate for 3 to 4 hours in advance. You can cook them right away, but letting them rest in the refrigerator will help them hold together during frying.

Take cakes out of refrigerator 15 minutes before cooking. Heat bacon fat or butter in a pan or cast iron skillet over medium heat until it sizzles when you add a small piece of bread.

Dredge the fish cakes lightly in flour, unseasoned breadcrumbs or panko and fry for about 5 minutes on each side, or until they are heated through and the outsides are crispy and light to medium brown. Salt to taste and serve with lemon wedges, tartar sauce or hot sauce.

Baccala' Alla Napoletana (Salt Cod With Potatoes In Tomato Sauce)

This is real Italian soul food — hearty and unrefined — and there are varieties on this recipe to be found all over Italy. Often, the potatoes are omitted and the dish is served over pasta.

Baccala' Alla Napoletana (Salt Cod With Potatoes In Tomato Sauce). Photo: Tom Gilbert/NPR

Makes 4 to 6 servings

4 medium starchy potatoes

1 cup extra virgin olive oil

1/2 cup black olives, pitted and roughly chopped

1 large Spanish onion, thinly sliced

Flour for dredging

1 1/2 pounds thick, desalted salt cod cut into large pieces

4 cups canned San Marzano tomatoes, with juice

1 tablespoon dried or 2 tablespoons fresh oregano leaves

1/2 cup white wine

Juice of 1 lemon

2 tablespoons salted capers, soaked, drained and roughly chopped

1/2 cup finely chopped parsley

Freshly ground black pepper

Salt

Peel the potatoes and boil them in salted water until slightly undercooked. Drain and slice into 1/4-inch thick slices.

Over low heat, sauté the olives and onion in a tablespoon or 2 of olive oil until the onions soften (about 5 minutes). Remove and set aside.

Raise heat to medium. Add the remaining olive oil to the pan. Dredge cod lightly in flour and fry on both sides until brown. Remove cod and set aside.

Add to the skillet the tomatoes, oregano, wine, lemon juice, capers and half of the parsley. Cook until sauce begins to thicken (10 to 15 minutes).

Add the cod and potato slices back to the skillet, turning them in the sauce. Cover with the onion and olive mixture. Add a few generous grinds of black pepper. Turn heat to very low and simmer slowly for 45 to 60 minutes, adding water in small amounts if the dish begins to dry out.

Sprinkle with the remaining parsley before serving; drizzle with more olive oil or add another squeeze of lemon juice if you like. Taste and correct for salt.

Bacalao A La Mexicana (Salt Cod With Onions In Tomatillo Sauce)

Because it uses very thick pieces of salt cod, this dish can be extremely salty. I used to try to moderate the saltiness by soaking the salt cod for an extra few days, but over the years I have grown to enjoy it with an aggressive salty bite. Feel free to turn up the heat as well by adding hot peppers or hot pepper sauce to the salsa verde. This recipe is adapted from Uncommon Fruits and Vegetables: A Commonsense Guide by Elizabeth Schneider (William Morrow Cookbooks, 2010).

Bacalao A La Mexicana (Salt Cod With Onions In Tomatillo Sauce). Photo: Tom Gilbert/NPR

Makes 4 to 6 servings

Salsa Verde (Tomatillo Sauce)

1 pound fresh tomatillos

2 or 3 ancho or other dried Mexican chilies (not chipotles)

3 garlic cloves, peeled

1 teaspoon tomato paste

1 bunch thoroughly rinsed cilantro roots and stems, chopped

1 bunch cilantro leaves, chopped

1 lime, juiced

Bacalao

1 1/2 cups salsa verde

1/4 cup extra virgin olive oil or more as needed for sautéing

2 large Spanish onions, sliced

Flour for dredging

1 pound desalted salt cod, cut into pieces approximately 4-inches square

4 cups cooked rice

Salt

For salsa verde, peel and discard papery covering from tomatillos. Rinse tomatillos well under running warm water to clean and remove sticky coating.

Boil 1 cup of water in a pot or saucepan. Clean dried chilies, discarding seeds and stems, and add them to hot water. Remove from heat and let stand for 15 to 30 minutes.

Puncture the tomatillos once or twice with a sharp fork and add to pot, along with garlic, tomato paste and chopped cilantro roots and stems. Cover and cook over low heat until tomatillos can be easily crushed. Allow sauce to cool. Add cilantro leaves and lime juice. Puree all ingredients in a blender or food processor.

For bacalao, heat oil in a pan or skillet over low heat. Add onions and sauté slowly, stirring frequently, until onions are translucent and turning a light golden color. Remove onions to a casserole or baking dish, spreading them to cover the bottom.

Dredge cod lightly in flour. Turn heat under skillet to medium, and brown cod thoroughly on both sides in the onion-flavored oil. Remove cod and arrange in casserole on top of cooked onions.

Reheat tomatillo sauce in skillet, scraping up remaining bits of flour, oil and juices. Pour sauce into casserole over cod and onions. Bake uncovered in 375-degree oven for 30 minutes. Taste and correct for salt. Serve over rice.

Nina's Cruzan Pickled Salt Fish

This dish must cure for a week before eating; after that, it will keep for a month or so in the refrigerator. My mother-in-law, Nina, used to leave it on the kitchen counter, which is fine if ambient temperatures stay under 65 degrees or so.

Nina's Cruzan Pickled Salt Fish. Photo: Tom Gilbert/NPR

1 pound desalted salt cod

2 bay leaves

1 medium red onion, chopped

1 red bell pepper, chopped

2 jalapeno, habanero or other hot peppers with seeds and interior ribs removed, finely chopped (leave seeds and ribs in if you like more heat)

2 celery stalks, chopped

1 cup thoroughly rinsed cilantro, including both leaves and stems, chopped

1 clove garlic, peeled

2 limes, juiced

1/4 cup light olive oil

Distilled white vinegar

Salt

Poach desalted cod along with bay leaves in simmering water to cover for 3 minutes. Drain, cool and flake. Discard bay leaves.

Add to a bowl the onion, bell pepper, hot pepper, celery, cilantro, garlic, lime juice and olive oil. Add flaked cod and mix well.

Spoon mixture into large mason or other glass jar. Fill to top with distilled white vinegar. Cover and refrigerate for 1 week. Taste and correct for salt. Serve on lettuce, crackers, toast or bread.

About Salt Cod

Buying. The quality of salt cod varies considerably. Often, what is labeled "salt cod," "baccala'" or "bacalao" is actually hake or another cod impersonator. You can make decent fish cakes using pretty much any of these, but for other recipes try to use the best quality salt cod you can find. This means nearly white whole fillets, about 2 or more inches thick in the thickest parts; these tend to come in wooden boxes packed in coarse salt.

Desalting. All of these recipes begin with desalting the salt cod. (You can skip this step if your fish seller — as some do in Italian and Latino markets — desalts the salt cod for you and sells it frozen.) This is done by soaking the fish in a pot of cold water for 2 days or so — changing the water 2 or 3 times a day. The pot should be kept in the refrigerator. Obviously, the thicker the salt cod, the longer the process will take.

Salt. Because the desalting process can be a bit unpredictable, do not add salt to these dishes until they are done and you have tasted them.

About the Author

Tom Gilbert writes about food, baseball, politics and the history of New York City. A longtime resident of Greenpoint, Brooklyn, where he is a notorious home cook, Tom knows the good food places in three NYC boroughs and several Italian regions; he can eat in eight languages and talk about eating in five.

codcod

Cod Comeback: How The North Sea Fishery Bounced Back From The Brink

Salt Cod: The Prosciutto of the Sea?

Forum: Mark Kurlansky discusses "The Food of a Younger Land"