The mysterious origins of a spicy, grilled fish dish

CHONGQING - In Singapore, the spicy dish is known as Chongqing kaoyu, or grilled fish. 

Served in a heated metal pan, a freshwater fish is stewed in a spicy, oily broth and blanketed with Chinese chillies mixed with numbing Sichuan peppercorns. 

It was love at first bite in 2011 when I discovered the dish at a popular supper street in Beijing during an internship. 

I remember the tantalising and intense fragrance of the broth and the silky texture of the piquant fish that stood in stark contrast to the crispness of its oily, grilled skin.

It was called Wushan kaoyu, referring to a picturesque mountainous county in the eastern end of Chongqing.

But 10 years later, when I returned to the capital city as China correspondent for The Straits Times, all my favourite roadside kaoyu stalls had disappeared. 

Restaurants selling the same spicy fish were aplenty, but to my puzzlement, they were calling the dish Wanzhou kaoyu. 

Wanzhou is a populous urban district in Chongqing’s north-east, about 175km away from Wushan, which is famed for its spectacular views of the Three Gorges along the Yangtze River. 

Still, whatever name it takes, kaoyu, which goes back thousands of years, has moved beyond China’s shores.

Tanyu, a popular kaoyu chain from Shenzhen with more than 400 eateries in China, opened its first overseas outlet in Singapore in 2017 and now operates four others in the Republic. 

And Shanghai-headquartered Bantianyao, with more than 1,400 outlets in China, has not only ventured into Singapore but also into Malaysia, Indonesia and South Korea. 

Within China, the grilled fish business is expected to hit 43.57 billion yuan (S$8.1 billion) in 2026, up 12.4 per cent from 38.76 billion yuan in 2025, according to Chinese consulting firm B&Y in Beijing, with chain shops accounting for 61.3 per cent of market share. 

The more time I spent in the country, the more I heard that Wanzhou is the birthplace of kaoyu. 

Online searches yielded articles that only reinforced this narrative, with none mentioning Wushan. 

Seeking answers in Wushan

Just as memories of the first grilled fish I savoured were starting to fade, a friend told me in December 2025 that it is a “little-known fact that kaoyu is from Wushan”. 

“When we were growing up, Wushan kaoyu was everywhere,” he said, adding that he did not know how Wanzhou eventually became known as the birthplace of kaoyu.

Determined to unravel the mystery, we decided on a whim to drive six hours to Wushan the next day in search of answers. 

We went out looking for kaoyu right after we checked into our hotel, but were confronted with a different type of fish: zhibaoyu, or paper-wrapped fish. 

In Ningjiang Road, which overlooks the Yangtze River and stretches for about 3.5km, eateries and riverside stalls sell mostly zhibaoyu. Tourists arrive in hordes on sightseeing buses and cruises that ply Eurasia’s longest waterway, with stops between Chongqing and its neighbouring Hubei province. 

We eventually picked a place that served zhibaoyu to satisfy our curiosity. 

The dish is served in a heated metal pan and made with similar spices, but the fish comes wrapped in parchment paper, which is said to trap and intensify the flavours.

Online, zhibaoyu is touted as a new generation and healthier form of kaoyu, with electricity instead of charcoal used to cook the dish.  

While the zhibaoyu was delicious, I missed the smokiness and the crispness of the fish’s skin in kaoyu. The colour of the broth was also more orange than the fiery red of the traditional kaoyu, with zhibaoyu’s flavours being generally less intense.  

I started to doubt myself: Did I really remember things wrongly? Is kaoyu indeed from Wanzhou and not Wushan?

A waitress in her 40s who grew up in the county provided some hints. 

“We used to say that Wushan is the birthplace of kaoyu, but that changed in the late 2010s, when Wanzhou claimed to be the home town of kaoyu and we subsequently switched to saying that Wushan is known for zhibaoyu,” she told me. 

“We do not know why the change happened.” 

Finally visiting Wanzhou

Is the answer in Wanzhou then? I had to find out. 

As I alighted at the Wanzhoubei railway station, I was greeted by billboards advertising kaoyu. One proudly proclaimed Wanzhou to be the home town of kaoyu, while another promoted a culinary school set up in 2021 for the local speciality.

I sought out Ms Lan Guifang, chairwoman of the local kaoyu industry association. She also runs Xiaojiumuzi Kaoyu, a three-storey restaurant in Wanzhou that can seat about 1,200 diners. 

Business was brisk at her restaurant on the Saturday I visited. Parked cars lined the street outside the restaurant and tables were full – families, couples and friends. Every table had a plate of steaming hot fish, and some even had two. 

Ms Lan explained that Wanzhou officially became the home town of kaoyu in 2018, after the local government applied successfully to the China Cuisine Association for the accolade and provided sufficient evidence.

Official records showed that the tradition of kaoyu in Wanzhou can be traced back to the Shang dynasty (1600BC to 1046BC), based on artefacts that contained fish bones, charcoal and green bronze pots. 

Kaoyu appeared again during the Southern Song dynasty in the 1200s, with records showing that a military cook once caught a fish by the riverside before salting and grilling it for the troops, and the method became increasingly widespread.

Subsequently, as cooking methods evolved, Wanzhou’s established steps of cooking the fish – which included grilling, marinating, stir-frying and stewing – were recognised by the national government as “intangible cultural heritage” in 2019. 

The official recognition helped to promote the local industry and solidified the district’s branding, added Ms Lan, who started selling kaoyu in 2002. 

Kaoyu is big business in Wanzhou, with official figures showing that the grilled fish industry exceeded 13 billion yuan in 2025, up from about 10 billion yuan in 2018. 

It includes fish farmers, kaoyu restaurants and companies that make ready-to-eat dishes and snacks, as well as seasonings for both home and commercial use.

The kaoyu culinary school in Wanzhou has trained and certified about 7,000 “kaoyu masters” as at 2024, and supported the creation of thousands of jobs.

Ms Lan recalls eating kaoyu as a child, when fish was only grilled and salted. Subsequently, in the 1990s, as China became increasingly wealthy, chefs began adding more spices to their kaoyu, creating the dish as it is known today. 

How then did Wushan get renowned for kaoyu? 

One theory among locals is that Wushan chefs were more willing to venture out to Chongqing’s main city and other parts of the country due to the county’s smaller population compared with Wanzhou. 

Wushan has a population of about 454,500, compared with Wanzhou’s 1.54 million. 

While the chefs left for job opportunities, they paid tribute to their home towns by naming their dish Wushan kaoyu. But they allegedly stopped doing so after Wanzhou became more famously associated with the dish.

Ms Lan said that the association is working on basic industry guidelines for operators to guarantee that diners are assured of basic standards – such as the size of the fish (minimum 1.75kg) – when stalls proclaim to serve Wanzhou kaoyu.

She describes good kaoyu as being free of the earthy taste common in freshwater fish. The ratio of oil and broth that the fish is stewing in should also be “controlled well”, she added.

A good marker is how kaoyu should not taste increasingly salty as the meal goes on, she said.

“The fish should instead become more flavourful as it absorbs the spices,” she added. 

The fish should be robust and succulent when diners start eating before becoming increasingly crispy and flavourful towards the end, when the broth becomes more condensed and the hotter oil cooks the meat further.

Locals top off the meal by adding noodles that soak up the oil. “That is the soul of the dish,” she said.

As far as I am concerned, I’m just glad that I accomplished my personal mission of uncovering how Wanzhou became known across China as the home town for kaoyu. 

The venture has satisfied not just my curiosity, but also my cravings for the dish.