Three truths and a lie about Japanese cuisine: In December 2013, Unesco added traditional Japanese cuisine to its Cultural Heritage list. One traditional sub-genre of Japanese cuisine includes dishes like spaghetti with ketchup and Salisbury steak, a ground-beef-and-gravy concoction that is a cousin of the hamburger. Raw horse meat sushi is a thing in Japan. The fortune cookie was invented in Kyoto in the 19th Century.

The lie? It was a trick. They’re all true, including the fact that there is a long-established cuisine in Japan called yoshoku that is made up of Western-style dishes with a Japanese bent to them. And while there are a few yoshoku restaurants in Great Britain and the United States, the cuisine is largely unknown outside of Japan, save for South Korea and Taiwan, two former Japanese colonies. How is this so?

Let’s rewind to 8 July 1853. That’s when Commodore Matthew Perry of the United States Navy sailed into Tokyo Bay. His mission: to convince Japan – isolated and closed off from the world for the last two centuries – to sign a trade deal. He was successful. Soon after, European powers signed similar agreements with Japan. And not long after that, the ruling shogunate was toppled for an emperor-based government known as the Meiji Restoration, which was much more favourable to the West.

Europeans and Americans began residing in some Japanese coastal towns to further hasten trade. Locals, somewhat undernourished at the time – since Japan was a poor, undeveloped nation (though hard to imagine now) and because, for the previous millennium, eating meat was largely prohibited – collectively came to the conclusion that the much taller, beefier Westerners were stronger and healthier than the Japanese. And so, the common wisdom at the time was that they should start eating Western food. In 1872, it was announced to the nation that Emperor Meiji had, in fact, eaten beef. And so began Japan’s fascination with Western food.

Furthermore, many of the Americans and Europeans in Japan at the time had a very colonial attitude toward Japanese food. Translation: they wouldn’t touch it. And so, local Japanese chefs, who had become private cooks for these newly arrived Western expats, learned how to make the cuisine of their European and American homelands. Many of those chefs ended up putting their own Japanese spin on the Western dishes. And yoshoku was born.

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Many people might be familiar with a popular yoshoku dish without realising it is part of the cuisine: tonkatsu: a breaded and fried pork or beef cutlet, not too dissimilar from a Milanese cutlet or Austrian schnitzel. The hambagoo might both sound and look familiar, except it’s not exactly what you think it is: it’s Salisbury steak, a bun-less patty of minced meat infused with onions and breadcrumbs, served with a demi-glace sauce. Interestingly, curry over rice, or kare raisu, was introduced to Japan by the British, who took it from India during the British Raj.

Perhaps the most beloved dish in the yoshoku cannon is omurice, an omelette stuffed with rice and served with a puddle of ketchup (which was popularised in the US in the early 19th Century) on top. It’s much better than it sounds. Speaking of ketchup, there’s also Napolitan: cooked spaghetti that’s rinsed in cold water then stir fried with vegetables and bacon and doused with ample amounts of the sweet sauce. Some believe the dish is derived from the French take on Neapolitan pasta called Spaghetti à la Napolitaine. It won’t taste anything like a pasta dish in Naples (or Paris, for that matter) but instead will have a smokiness from the bacon, a sweetness from the ketchup and sometimes a slight kick from the pepper sprinkled on at the end. And unlike pasta dishes in Italy, the pasta is cooked beyond al dente to a flaccid texture. The result is a marriage of sweet, spicy, smoky and umami that tastes way better than it sounds.

It wouldn’t take long before some of those Japanese chefs opened up their own restaurants serving this “Western” cuisine. The first was the now-defunct Ryorin-Tei in 1863, located in foreigner-rich Nagasaki. After the turn of the 20th Century, yoshoku was geared toward wealthy Japanese; yoshoku restaurants were often located on the top floors of posh shopping malls.

However, in post-war Japan, yoshoku became the country’s de facto comfort food, and people of all classes began eating it at home. Children favoured Napolitan and omurice. Yoshoku restaurants eventually came down from the top floors of upscale malls and into casual, no-frills eateries.

“After World War Two, people were poor in Japan,” said Taro Noguchi, chef and owner of his eponymous Michelin-starred restaurant in Osaka where he peppers the menu with yoshoku dishes along with some Osaka staples. “Yoshoku was a trend in those days because it was affordable and easy to make.”

Joseph Moon, owner of the yoshoku restaurant AOI Kitchen in New York City, agrees. The appeal, he said, is all in the balance. “Yoshoku is one of the earliest forms of Asian-Western fusion food. Simply put, it is Western food that goes well with rice. And rice is the staple of Asian cuisine. It’s well balanced with the old and new, Eastern and Western. Western food might come across as heavy for most Asians. So, with some Asian ingredients involved, it neutralises the heaviness a bit.”

South Korea, where Moon’s family hails from, also has a yoshoku food tradition since it was a Japanese colony in the first half of the 20th Century. “It gives me a very nostalgic feeling when I eat it,” said Moon. “And that’s the kind of feedback we get from our customers, who are mostly Asian.”

Translated as “Western food”, yoshoku is something of a misnomer. Sure, the food is “Western” in the way that Tex-Mex is “Mexican” or chop suey is “Chinese”. It’s a cuisine filtered through the lens and palate of the Japanese. 

“These are only nominally Western dishes at this point,” said American writer Tom Downey who has written extensively on Japanese food and culture. “They’ve been unmoored from their origins for so long that they’re Japanese. Yoshoku relies on a lot of lard and other ingredients that are not so fashionable anymore in the West.”

What makes yoshoku so intriguing today is that the dishes have hardly evolved, making experiencing the cuisine like eating in a time warp back to the late 19th or early 20th Century. After all, Americans relegated Salisbury steak to the TV dinner decades ago, not to be found outside of the bottom shelf of the freezer section in suburban grocery stores.

Amazingly, yoshoku is still very popular in Japan, as well as in various big cities around the world where Japanese expatriates live. In Tokyo, Taimeiken has been serving up yoshoku classics since 1931. Even Denny’s, that icon of mass-produced American diner fare, serves up a large selection of yoshuku staples throughout Japan.

However, in 21st-Century Japan, attitudes towards Western cuisine have changed. Now you can find first-rate Neapolitan pizza that might rival the pizza in its birthplace as well as three Michelin-star French fare. Tokyo and Osaka are now among the best dining cities on the planet, both for Japanese and Western cuisines.

So, the idea that eating Western food will make the Japanese stronger and healthier is long gone – after all, Westerners are more likely to view Japanese cuisine as healthier these days – but the notion lasted at least until the 1970s. It wasn’t until Japan’s economic boom, when restaurants serving actual Western food – not yoshoku – began opening up in the country for the first time. On 20 July 1971, the first McDonald’s in Japan fired up its grills in Tokyo’s Ginza district. The man responsible for it, one Den Fujita, was naively optimistic about the health benefits from the ubiquitous burger chain, saying: “Japanese are poorly built because they eat rice. We’ll change that with hamburgers.”

Nevertheless, yoshoku persists and remains a beloved part of the Japanese cooking and dining landscape.

“When yoshoku is good it’s very amazing,” Downey said. “The thing about yoshoku, as with all the things and places that are really high quality in Japan, they focus on all the little details that most people wouldn’t put much thought into” – such as learning ways to coax flavour out of every ingredient in a recipe, all the way down to that stalk of parsley on your plate.

“The best places focus on the perfection of the dish,” he added. “And that’s what makes yoshoku so interesting.”

Culinary Roots is a series from BBC Travel connecting to the rare and local foods woven into a place’s heritage. 

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