Ueno will host a pop-up at MO Bar at Landmark Mandarin Oriental, Hong Kong until the end of October.

“We care about the small details,” Ueno adds. For example, when he gives customers a glass of water, he puts a small cube of ice in, which he says tells him when the customer has finished the water (“there’s a clink”).

Ice and water are central to any bartender’s work. Ueno elaborates: “One quarter of the drink is water, so the quality of the water in the ice actually determines the taste of the cocktail.”

Water is also an ingredient, says Endo.

“If it tastes watery, it’s because it wasn’t mixed well. Think of it as mayonnaise. It’s an emulsion; the egg and oil should not be separate.”

Many Japanese bartenders make their own ice, and it could take up to four days to make a perfect, crystal clear, airless block, which is cut down into smaller cubes.

It’s believed that these slowly formed blocks of ice won’t melt as easily. “If you order whisky on the rocks, you want to taste the whisky, not the water,” says Hiidome, who uses a special alkaline ionising filter for his water for a “smoother” texture.

Hand forming ice into cubesand various other shapes with ice picks and knivesis a key part of a Japanese bartender’s repertoire.

Hiidome creates heart-shaped ice for couples on dates, and Ueno is known by bar enthusiasts for his “ice diamond”, but ice is also vital in another technique, the hard shake.

Endo says that the technique, for which Japanese bartenders are known, aerates the drink, making it more gentle on the palate. Always done in a cobbler shaker, a three-piece shaker with a cup, strainer and small cap, it tends to be a series of fluid, elegant moves, designed to minimise large cracks in the ice cubes,and instead, create small shards that end up floating on top of the beverage.

“It’s a softer touch, and the drink is smooth and easy to drink. At the beginning [when the technique was first used], people said it was wrong, but now it’s become one of the special ways Japanese bartenders use to make cocktails,” he says.

However, every bartender’s moves are different. Hiidome insists on a “three-point” shake, with vigour, indicating the different heights of his moves; whereas Ueno’s shake shows clearly controlled deceleration; and Endo’s is more like gliding, rhythmic brush strokes.

The differences don’t end there. Ueno’s service style is playful, often joking and chatting with customers, bucking the “quiet bartender” image, and he wears his hair like Elvis, while Endo insists on a formal ivory jacket, tuxedo shirt and black bow tie, and makes his cocktails in complete silence.

Japanese bartending is mostly known for its classic cocktails, but some bartenders, like Hiidome, are better known for their seasonal fruit beverages. On the long counter at b.a.r. Executive Bar, there is a fruit bowl displaying the best seasonal produce Hiidome can find. He insists on using only Japanese fruits.

“I’ve tried fruits from other countries, but in my opinion, Japanese fruits have good flavour and aroma. I never add syrup to the fruit drinks, and with Japanese fruits, I never need to.”

While Endo feels his training has mostly been in the classic styles, his signature drinks are all new creations, born out of participation in cocktail competitions. Coming from Fukuoka in southern Japan, far from the epicentres of Japanese bartending of Yokohama and Tokyo, made him more curious about what was happening in the rest of the country.

“Competitions help because they let me know where I am compared to the best in the country,” he says. Now that he’s in Hong Kong, he doesn’t compete, but continues to create new drinks every day.

Endo says that Japanese people, bartenders and customers, tend to be more conservative, but that is slowly changing. “Some may refuse [to use] new ideas, but many younger bartenders in Japan are being more creative. [Like American or European bartenders] they are also experimenting with molecular techniques, new equipment and those sorts of things. It’s not really my style and I don’t have the equipment, but think I would like to if someone taught me how to use them,” he says.

Both Endo and Hiidome speak of throwing, a technique that came into fashion recently. It involves pouring the drink from one vessel to another, increasing the distance in between the vessels as one pours, not unlike the tea pouring technique used in Malaysia and Singapore. “The basic techniques we use are stirring, shaking, building, blending, and now, throwing,” says Hiidome. “Throwing is actually a very old technique,” says Endo. The roots of the technique are varied and hard to trace, but the modern interpretation appears to have been brought back by Cuban and Spanish bartenders, the intention being that it creates fine air bubbles in the drink.

Whatever techniques they use, Japanese bartenders always go back to what is important: the customer’s enjoyment.

“When a guest comes into the bar, it should be like stepping into another world. They can forget their normal life. They should feel happy and comfortable,” says Endo.

Bar High Five pop-up until October 31

The Shell at MO Bar, The Landmark Mandarin Oriental, The Landmark, 15 Queen’s Road Central, Central,tel: 2132 0077

Mizunara: The Library

4/F Kiu Yin Commercial Building, 361-363 Lockhart Road, Wan Chai, tel: 3571 9797

b.a.r. Executive Bar

27/F Bartlock Centre, 3 Yiu Wa Street, Causeway Bay, tel: 2893 2080

Butler

5/F Mody House, 30 Mody Road, Tsim Sha Tsui, tel: 2724 3828