At the far end of the L-shaped space – barflies may remember it as the former location of the nightclub Mudita or, previously, Fly – a dividing wall made to resemble blocks of frozen ice cubes gives a gentle nod to our location on the historic Ice House Street.

The sound of drilling occasionally punctuates the conversation, while bartenders polish and stack away delicate glassware in front of a loaded backbar.

The bar will be one of Gokan’s biggest launches to date, bringing together an Avengers-style line-up of top talent: Zaiyu Hasegawa of Tokyo’s two-Michelin-star Den will work with Tsukasa Uraguchi, former chef of Hong Kong’s two-Michelin-star Arbor, on a food menu that will launch in September, while heading up the bar will be Kaito Ohba and Morris Chang, formerly of Osaka’s Bar Beso and Hong Kong’s Penicillin, respectively.

“Considering the size and scale, it’s quite [a lot] bigger than what I usually do,” Gokan admits.

Gokan never originally planned to go into this business. In another life, he might have been top brass at his father’s electronics manufacturing business in Japan.

“I had no dream,” he says, thinking back to his teenage years when he, as the family’s only son, was grappling with the expectation that he would take over his father’s company. “I kind of had no choice.”

He took a more pragmatic approach. If being in the family business was in his future, he recognised that it would probably be beneficial to gain some work experience.

At 18, he interviewed for pastry chef and bartender roles and ended up working at a popular high-volume bar in Japan. He was offered a manager role by the time he was 20.

“It was quite a rare experience for a young kid, because you can learn how to hire people, train people, run a business,” he says. “So I decided to take it.”

He kept going and eventually a regular guest planted the seed of an idea to go to New York. He decided he would give it a shot but was acutely aware that while he had five years of bartending experience, he did not have any “special skills”.

“Back in the day, there wasn’t really YouTube or social media, so I wasn’t sure what was popular or what was happening in New York.”

He did not want to land in America without something up his sleeve, so he decided to train in the art of the tea ceremony, something his grandmother would perform back at home.

“Some people say tea ceremony is like the root of Japanese bartending. Japanese bartending culture is only around a hundred years [old], but tea ceremony culture is thousands of years [old]. So a lot of Japanese bartenders take it as a reference.”

He also became deeply interested in sherry after coming across a sherry bar in Japan. He was so impressed by the fortified wine’s taste, culture, history and technique that he decided to learn more about it.

He says sherry was not widely known or appreciated in Japan back then, even among sommeliers.

“Sherry was kind of like an item between bartender and sommelier. But no one really touched it.”

He eventually left for New York in 2006, aged 23, with zero English skills. Not only would he build his fluency, he would end up working for the famed speakeasy Angel’s Share for a decade.

It was six years into his life in New York that everything changed.

“In the beginning there was no chance to use those [tea ceremony and sherry] skills,” he says. But things fell into place when he created a cocktail for his entry into the Bacardi Legacy Global Cocktail Competition in 2012. He used his memories of his grandmother’s tea ceremonies and his love of sherry to create a recipe incorporating two kinds of rum, Pedro Ximenez sherry, matcha tea and yuzu zest.

“The idea was kind of introducing my background and what I learned before,” he says.

He won, beating 25 other competitors from around the world. The drink, Speak Low, became the name of the first bar he opened, in Shanghai, in 2014 – a reminder of how the cocktail changed his life.

With his new Hong Kong bar, Gokan now has 10 in his stable – the ninth, SG Tavern in Tokyo, recently opened – as well as liquor brands SG Shochu and Kokuto de Lequio, and even a new glassware brand, Sip and Guzzle.

“I always like facing a challenge. I am doing something new every time,” he says, referring to how each of his openings tackle something different.

Tokyo’s SG Club is divided between two floors (“Sip” and “Guzzle”) representing contrasting styles of drinks. Swrl, also in Tokyo, sells “wine cocktails”, and Okinawa’s El Lequio highlights the curious history of the seafaring Spanish and Portuguese during the Ryukyu Kingdom era (1429-1879).

“When I open a new bar, we take a lot of different recipes from each [existing bar] because we have a lot of different bars,” Gokan says. “But we did not do it this time [with Gokan] – we’ve developed a new drinks menu from scratch.”

This is partly because customers these days are so well travelled, he says, especially Hongkongers, who frequently visit Tokyo, Shanghai and New York, where his bars are.

“There are so many people coming to my bars, and some of them already know about Speak Low, Sober Company, SG Club. Even on the first day, they look at the menu and they’re like, ‘Oh, I’ve tried this.’

“I don’t want to [anger] people, like, ‘Oh, Shingo is making the same drink again,’” he laughs.

While Gokan is keeping quiet about the new bar’s final cocktail menu, he says that it will be centred on gomi, the five tastes of Japanese cuisine: sweet, sour, spicy, bitter and umami.

“When you look at the menu, I think you will get the image of the drink. Visually, it’s not very complex, but the flavour is pretty complicated. We use very good glassware – my opinion is, if you use very good glassware, you don’t need to have a lot of garnishes.”

One of the signature drinks he is excited about is Gokan’s take on the Rebujito, a sherry-based cocktail that he loves but says is underrated.

“Even bartenders don’t really know about the Rebujito. It sounds like mojito, but it’s completely different. The classic is [made with] fino sherry with 7-Up or Sprite, and it’s more like a festival drink.”

The Rebujito at Gokan is made with dry manzanilla sherry, housemade pink guava soda, sonic (a mix of tonic and soda water) and a touch of marigold.

“It’s very simple, but it’s super delicious. That’s the drink that I want everybody to get.”

There will also be a whisky sour with a base of whisky, amaretto and black truffle that will be nurtured through what Gokan refers to as the solera technique.

“We’ll keep adding [to the base] at different times and use it as a base for our whisky sours.”

In the world of sherry, the solera system is a method of fractional blending used to ensure a consistent flavour profile. Barrels are stacked in rows, and new wine from the top is regularly added to older wine in the barrels below, ensuring the characteristics of the sherry are maintained.

You cannot help but think that Gokan’s entire universe has been one giant solera system, with every new experience, skill and piece of knowledge trickling down to add complexity to, but not changing, the heart of his craft.

It makes sense now why he settled on Gokan as the name of the bar.

“It’s very personal. It’s a collection of everything I’ve done so far.”

Gokan, 30 Ice House Street, Central