Bar Gen Yamamoto, a tiny ground-floor space tucked in the shadows of Tokyo’s glitzy Roppongi district, has quickly become one of the city’s most buzzed-about new craft cocktail bars.

But forget what you know about the cocktail bar. There are no suspenders and mustaches, no theatrics, no indie rock or 1920s jazz—no music whatsoever. The bar, which is carved out of a 500-year-old Mizunara (Mongolian oak) tree, seats only eight.

The experience of drinking at Bar Gen Yamamoto is far more like dining at one of Tokyo’s intimate, chef-driven kappō restaurants than any Western concept of a watering hole. This is precisely why it might come as a surprise to discover that Gen Yamamoto, the bar’s owner and sole bartender, spent seven years in New York City and New Jersey bartending at restaurants like Soba Totto, En Japanese Brasserie and David Bouley’s Brushstroke.

Increasingly frustrated with the limited variety of produce he was finding in the U.S., Yamamoto decided to return to Japan to apply many of the techniques he learned in America to a Japanese palette of ingredients. At Bar Gen Yamamoto he employs everything from fava beans to kabocha squash to hōzuki (tart winter cherries) to local spices and fresh herbs like ki no mé (leaves of the prickly ash, which lend an aromatic, almost medicinal flavor). Kuzu (Japanese arrowroot) is used to create viscosity and texture; wasabi cuts through tart citrus; and pipa-chi, a cinnamon-like spice from Okinawa, adds bite to spirits like kumquat and sweet potato shōchū. Through his use of local ingredients he serves up original seasonal cocktails reflecting the diverse flavors of Japan.

While a stylistic emphasis on local ingredients and seasonality might not seem like a surprising approach to bartending in a place like San Francisco, it’s remarkably novel within the context of Tokyo’s cocktail scene. The Japanese style of bartending is inherently meticulous (sometimes spectacularly so), and often driven by the perfection of classics and the mastering of technique. Kazuo Uyeda, one of Japan’s most prominent bartenders, is still best known for his rhythmic shaking style (called the “hard shake”), colorful drinks and quirky garnishes; while Hidetsugu Ueno, of Bar High Five, is famous for carving intricate ice diamonds for individual cocktails.

What’s garnering Yamamoto so much local attention is his more subdued, naturalistic approach and his studious understanding of each ingredient. He found that, for example, working with a bottle of sparkling nigorizaké (unfiltered saké) the top half had a different flavor profile than the bottom half. Traditionally the bottle is lightly shaken before it is opened, but Yamamoto refrains from mixing up the contents and chooses to separate them instead, using the two parts in different ways. The bubbly, more delicate top-half might be mixed with fresh mango juice to add brightness to a drink, while the richer, creamier bottom-half might be combined with a nutty edamame puree to intensify the saké base.

Yamamoto’s emphasis on presentation is also an integral part of the experience. Each drink is served on a lacquered tray spritzed with water and decorated with seasonal greens. And his glassware collection includes everything from delicate porcelain to handblown vessels layered with paper-thin bands of color to glasses cut in the traditional kiriko style of Tokyo.

This combination of details—and the quiet of it all—is certainly unique in a Western context, but it’s also a departure from the experiences often expected from Tokyo cocktail bars. For both cultures of bartending, Gen Yamamoto’s hyper-seasonal, almost monastic approach to drinks offers a new path that, while divergent, is nothing if not uniquely Japanese.