"Now that is secret," the chef says cryptically as we chug down the silty Thu Bon River.
He is seated at the stern of the crimson fishing boat, his gaze locked on lithe fishermen casting their nets in the murky waterway in central Vietnam.
I am inquiring into the recipe of a famous Hoi An speciality, cao lau, or rice noodles drizzled with a salty-sweet braise sauce, topped with tender soya-stewed pork, an aggregation of herbs, bean sprouts and crispy crouton squares.
Greylag geese paddle by serenely as we boat away from my charming villa accommodation within Red Bridge, a reputable restaurant- cum-cooking school in Hoi An.
Its rustic, open-view kitchens nestled amid river thickets are fading into the distance, but there are still faint aromas of local cuisine.
As it turns out, the chef is not deliberately furtive about the cao lau recipe.
"The exact noodle recipe is held secret by fourth-generation descendants of the first cao lau creator," he says. "No one else really knows how to achieve that perfect chewy consistency."
Water from ancient wells, he adds, is blended with lye ash from trees sprouting on the neighbouring Cham Islands, ensuring the creamy-yellow tinge and distinctively al-dente texture of cao lau.
Even the origins of cao lau remain mysterious. The noodles, which some say resemble udon, could have been influenced by the Japanese; the braised meat by the Chinese; the crackers, like croutons, by the French, a restaurateur tells us later.
"And of course, the mound of fresh herbs? Distinctly Vietnamese," he adds.
Twenty minutes fly by and our boat arrives at Hoi An Ancient Town, a beguiling Unesco World Heritage site.
The chef alights for Cho Hoi An, the central market, to buy fresh produce and to receive a group of cooking class students.
As my family and I navigate the roads in the searing heat, I cannot help but ponder how cao lau embodies the cultural layers of this old- world Vietnamese town.
Lining the streets are Chinese shophouses with ochre-coloured walls and mahogany roofs, interlaced with emblematic Japanese bridges, merchant houses and buildings with French colonial influence and louvred windows - all multifarious indications of Hoi An's melting-pot heritage.
"Four hundred thousand dong (S$24), one-hour ride," calls out a driver clad in a sky-blue shirt at the Ancient Town.
Perched on the seat attached to the rear of his three-wheeled cyclo, he pats his fiery-red passenger seat and adjusts the shamrock-hued shade, telling my family his price is a good rate.
But we decide that today, we will navigate the town centre, a lattice of just seven streets, by foot. The lanes are closed to motorised traffic, a refreshing change from the chaotic traffic that characterises major Vietnamese cities.
A lean, sun-bronzed man points to his rickety sampan, touting a ride down the Thu Bon River.
A few steps away, a woman brandishes leather swatches in front of her lantern-laced store, telling me: "Good leather - make shoes."
The fierce onslaught of sales pitches forces a first impression that Hoi An Ancient Town exists mainly for the foreign visitor.
We fly from Singapore to Danang International Airport on SilkAir (www.silkair.com) and take a half-hour car transfer to Hoi An.
We stay at a private three-bedroom villa in a compound that is part of Red Bridge Restaurant and Cooking School in Hoi An (www.visithoian.com) for five nights. The villa rate is US$275 (S$375) a night.
Hoi An Ancient Town, located 2km from Red Bridge, is accessible by a five-minute taxi ride or a 20-minute boat ride along the Thu Bon River.
The best time to visit Hoi An is between February and May, when the weather is mild with moderate temperatures, low humidity and rainfall.
We visited in June, when the temperature rose to a searing 37 deg C. Avoid the rainy season from September to January.
But as I spend time in the colourful municipality - where travel agents, tailors, shops, eateries and inns occupy every turn - I realise the deal today is not inconsistent with Hoi An's heritage of attracting travellers.
Between the 16th and 19th centuries, Hoi An, then known as Fai Fo, was a magnet for South-east Asian trade, attracting Chinese, Japanese and European merchants who sailed from the South China Sea to the Thu Bon River to trade porcelain, silk, spices, precious metals and oils.
The confluence of cultures stamped itself on the town - merging local traditions with the architecture of the foreigners who stayed.
I pause at the House of Tan Ky (101 Nguyen Thai Hoc Street), built 200 years ago by an ethnically Vietnamese family, well-conserved and lived in by seven generations of descendants.
A guide describes the Japanese crab-shelled ceiling and peaked roof, fine Chinese poetry and Oriental carvings on roof beams, and Vietnamese crosshatch top support.
"Look at those grape leaves," she says of the European motif that has embellished the timber balcony over the years.
As the Thu Bon River estuary silted up in the 19th century, traders stopped coming in droves.
The town was severed from outside influences for decades and the town architecture was largely untouched by the impact of modernisation.
Just as cao lau is an apt metaphor for Hoi An's cultural heritage, the Ancient Town is today a living museum displaying the intriguing convergence of cultures.
Hordes of tourists are crowding the pink-hued Japanese Covered Bridge, or Lai Vien Kieu, arguably the most iconic attraction in Hoi An.
Flanking one end are twin sculptures of dogs and monkeys, both sacred symbols in ancient Japanese culture, we are told.
Tailoring is now the lifeblood of Hoi An, a logical evolution of what was once a major silk trading post.
I pop into several tailor shops, amid the mind-boggling 400 in town, and attempt to settle on a good tailor, with preferred fabrics and skill sets.
"Come," a woman gestures at me surreptitiously, after I express interest to customise a dress.
Behind the curtain, she points to a large basket of white, wiggly silk worms feeding on mulberry leaves. "Soon, these worms spin cocoons and make silk.
"Real silk," she adds.
We focus on another of Hoi An's well-known facets - its cuisine - and begin by exploring the markets at the Ancient Town.
Faces under conical hats peer out at me and gnarled fingers signal towards vast baskets of tropical fruit on display. I feast on magenta dragonfruits, butter-yellow mangos, emerald-hued calamansis and ripe custard apples, all brilliantly sweet and refreshingly juicy.
"In Hoi An, we eat fresh from the land," a local tells me and I consider how the overused farm-to-table catchphrase is actually tenable here. "Rice flour is milled from scratch at the nearby paddy fields and fruit and produce are always local and fresh."
Local ingredients are undoubtedly crisp, but as with cao lau and many elements of this town, offshore influences are highly apparent in its famous dishes.
In Hoi An, situated midway between Hanoi and Ho Chi Minh City, Oriental flavours of the north intersect with Cambodian influences of the south, tinged with a French colonial touch.
At a restaurant, I sample banh bao vac, or steamed white rose dumplings, tiny balls of shrimp, minced pork, mushrooms, onions and bean sprouts, wrapped into a ruffled scallop of rice flour dough, then steamed and topped with deep- fried shallots and dipping sauce.
They are thinner and lighter than the traditional Chinese dumplings I am familiar with.
The century-old recipe is held secret by a single Chinese family at 533 Hai Ba Trung Street, which painstakingly hand-makes 6,000 dumplings a day and dispatches them to eateries all over town.
Nearby, people are squatting on stools by the roadside to enjoy xi ma, or black sesame paste, another closely guarded recipe held by the family of centenarian Ngo Thieu, its creator and living local legend.
My family returns to our villa for a quiet dinner, where we grow to love stir-fried morning glory - a type of water spinach, not the flower - a ubiquitous local green that is sauteed with garlic.
We are enthralled by the in-house herb garden, a plot of growing greens that will soon adorn dinner platters - lemon basil, cinnamon basil, cilantro, coriander, water spinach, fish mint, scallions, chives, parsley and celery.
An instructor teaches a class to make banh xeo, a savoury rice-flour crepe, folded over stuffed herbs, shrimp, pork and bean sprouts.
As I dip my feet in the pool, an American relaxes on a sunbed, recounting her class experience and enjoying her creation, served with peanut sauce. Banh xeo looks like an omelette and I am surprised there is no egg involved, just powdered turmeric.
Over the next few days, my family and I head daily to the Ancient Town, where we feast - in between fittings at the tailor - on both street and gourmet food specialities.
At Morning Glory (106 Nguyen Thai Hoc Street), a restaurant established by Trinh Diem Vy, a renowned local chef, we unanimously agree that the mackerel cubes, wrapped in banana leaf with chopped wood-ear mushrooms and turmeric, as well as the five-spice pork belly, are stand-outs.
Another day, my husband makes a quick detour to locate a store famous for its banh mi, a popular local baguette of French origin, but made with a local twist - using rice flour in addition to wheat flour.
"A symphony in a sandwich," American celebrity-chef Anthony Bourdain had proclaimed of the baguettes made at Banh Mi Phuong (2B Phan Chau Trinh).
We try an assortment of banh mi and discover why the original - with delicious grilled pork, pork liver pate, meat floss, cheese, pork patty, cilantro, mint, spring onion and topped with a secret homemade dressing - is most sought after.
We experience the most internationally influenced food at Mango Rooms (111 Nguyen Thai Hoc Street).
Its chef and proprietor Tran Thanh Duc whips up an array of delectable dishes marrying East and West, such as Pearl of China Seas (tempura-battered prawns tossed in garlic butter) and La Cubana (beef cubes flame-broiled with Cuban rum and served with Latino-style salsa).
The fern-green and teal walls and vividly coloured cushions and chairs evoke a laid-back vibe somewhat reminiscent of the Caribbean, as we watch boats bobbing on the Thu Bon River.
Chef Tran's outfit perhaps epitomises the way forward, as locals begin to venture abroad and tourism demands the fusion of old and new.
On our fifth and final morning in Hoi An, our in-house villa cook asks for our last breakfast order.
My family requests individual breakfast staples they have enjoyed, both Western and Vietnamese, but I am indecisive.
"Choose something you will remember Hoi An for," the villa manager prompts with a smile.
I pause for a moment, mentally racing through the contrasting flavours and worldly influences of Hoi An cuisine.
I decide on cao lau.
A version of this article appeared in the print edition of The Sunday Times on October 09, 2016, with the headline 'Hoi An on a plate'. Print Edition | Subscribe
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