For the Portuguese, salted cod is more than just an ingredient: it’s a way of life. Isabel Vincent finds comfort in the food wherever she is in the world

I grew up in a Portuguese immigrant household in Toronto in the 1970s, where we ate bacalhau several times a week. You might not be excited by the idea of eating salted cod every other day, but for my family it was a reminder of where we came from. Occasionally we’d eat bacalhau at Portuguese restaurants, where they would prepare it in a casserole with shredded carrots and cream, but it always seemed wrong to me. Bacalhau was something to devour at home: the slabs of fish doused with olive oil from the faux-crystal decanter my parents would top up from a large yellow can.

Bacalhau in Portuguese (or bacalao in Spanish) has long been a staple in the Mediterranean. Brought to the region by Basque fishermen and traders in the late 1400s, today, thanks to stricter limits on fishing, it has become a high-priced delicacy in Iberian cuisine. The fish, which is split open, dried and salted after it has been caught, is tied to the peninsula’s identity. Miguel de Cervantes wrote about it in “Don Quixote” and in 1884, while living in Paris, the great Portuguese writer Eça de Queiroz wrote a letter to a friend in which he described how he yearned for bacalhau smothered in caramelised onions.

My father bought it from the Portuguese fishmongers found in Kensington Market, the city’s immigrant enclave. Although we lived in the suburbs with its orderly supermarkets and immaculate lawns, every Saturday morning we’d drive to the market, on the border of Chinatown, to visit its rickety shops stocked with specialities from around the world. My mother was a regular customer at Global Cheese, where staff would ply us with sample slices of different varieties before she would make her purchases.

A touch of salt Bacalhau on sale at a market in Lisbon, Portugal

But it was the row of fishmongers, with their linoleum floors covered in sawdust, that my father visited. He was such a good customer that the owners would invite him to the back of the shop to peruse the splayed salted planks of dried fish, stacked like pieces of plywood in the storage room. Once my father had made his choice, the fishmonger would cut through the prized slab with a table-mounted electric saw, revealing the dense firm flesh beneath the dusty layer of salt. Finally, the freshly sliced fish would be laid onto thick sheets of waxed paper for my father to take away.

At home we’d set up a large bowl of cold water on a shelf in the wine cellar - where my father kept barrels of home-made red wine and an entire leg of prosciutto - and place the slabs of fish in to soak. Over a 48-hour period we would regularly have to change the cloudy mixture until it turned clear, taking the excess salt with it. This wasn’t my favourite part of the process.

My parents prepared bacalhau in lots of different ways: boiling it with potatoes and serving it with minced garlic and olive oil or barbecuing it over charcoal and serving it with parsley (and yet more garlic-infused olive oil). On special occasions my mother made croquettes called pasteis de bacalhau by whisking pieces of flaked fish with mashed potatoes, egg yolks, chopped parsley and onion, before folding in beaten egg whites and dividing the mixture into small ovals to deep fry. We also ate it in a soup called açorda, which is made from coriander, thin slices of stale bread, garlic and olive oil. The original recipe for açorda was passed down from the Moors who occupied Portugal between the 8th and 13th centuries. Later, when bachalhau arrived in the region, the Portuguese began adding it into the mix. My parents were proud of this tradition and never failed to tell my brother and I that not only was bacalhau one of the healthiest things you could eat, but an ancient part of our heritage. Bacalhau, they’d tell me, was the food that had made it possible for Portugal’s greatest explorers to survive at sea.

Fine fish fritters Pasteis de bacalhau

Despite being an Iberian delicacy, it was the Vikings who first preserved cod by drying the fish in the Arctic air, later rehydrating and eating it during their voyages to Greenland and Iceland. But it was the Basque fishermen who introduced salt to the preservation process. Portuguese, Breton and English fishermen soon copied the technique, and, as my father was fond of reminding us, explorers took it on their voyages to the New World.

During the 18th century, salted cod was plentiful. Transatlantic trade saw it become a common food not only in Europe and the Mediterranean, but in the Caribbean and Brazil too. By the middle of this century a series of British restrictions on cod-fishing rights on the Grand Banks of Newfoundland led to revolutionary fervour among New England merchants who traded salted cod for molasses in the West Indies. Fishing rights were so vital to the wellbeing of the British colonies in New England that the restrictions helped spark the American revolution in 1765. Today you can still find a large carved wooden replica of the “Sacred Cod” suspended above the chamber of the Massachusetts House of Representatives in Boston: a “memorial to the importance of the cod-fishery to the welfare of this Commonwealth.”

While bacalhau has shaped international trade for thousands of years, it’s also been important in my own life. Some years ago I began working as a reporter in New York City. Mourning my mother’s death and the end of my own marriage, bacalhau helped me heal. One rainy Sunday afternoon in 2012 I took a train from Penn Station to Newark’s Ironbound district, a Portuguese neighbourhood dotted with restaurants and boutiques selling effigies of Saint Anthony, the patron saint of Portugal, to buy my beloved bacalhau.

When I returned home I soaked it for days, just like we had in my childhood home. Then, without working to a recipe, for the first time in my life I recreated the pasteis de bacalhau my mother made. My only guidance? A distant childhood memory of her at work in the kitchen. As I removed the first batch of golden brown croquettes from the oil and set them on a paper bag to drain, I split one open and savoured my creation. Crunchy and sublime with a hint of salt, they offered immediate comfort, transporting me to happier times in an instant.