These premium varieties—all produced under the supervision of former Japanese soccer star and now accomplished sake connoisseur Hidetoshi Nakata—have been such a hit that they’re now releasing a brand new alcoholic Kit Kat called Bijofu Yuzu Sake.

Yuzu is a popular Japanese citrus with a deliciously unique sour flavor that’s said to taste like a combination of grapefruit and lime. That’s not to say that it truly tastes like either of those things, though, as yuzu is unique, and its flavor is so adored you’ll find it in everything from teas and marmalades to spicy pepper and soba broth. The dimply yellow fruit is also used to make yuzushu, a liqueur that can be enjoyed on its own or with ice or a mixer.

Koichi Prefecture is the country’s largest producer of yuzu, and it’s also home to one of Japan’s best yuzushu varieties, created by local brewery Hamakata Shoten.

While many yuzushu liqueurs are created with a white spirit base, Hamakata Shoten’s yuzushu is made with a sake, or Japanese rice wine base. This gives the drink a richer and more complex flavor that lifts it way above other competitors on the market.

Hamakata Shoten’s yuzushu is named "Bijofu Yuzu." Bijofu translates to "beautiful, strong and kind." Bijofu’s mix of sake and freshly squeezed yuzu juice has a sweet and tart, zesty, refreshing flavor, and this is exactly what the new KitKats will taste like. Their special recipe will be kneaded into the wafers and their white chocolate coating to create a KitKat that’s both sweet and sour, and packed with yuzu flavor.

To find out more about the story behind the new KitKats, and Nakata’s involvement in the project, take a look at the video above, which comes complete with English subtitles.

Unlike the other two alcoholic KitKats in the Premium Sake series, the Yuzu Sake Kit Kats come with a slightly lower alcohol content of 0.2 percent alcohol. This gives them such a smooth flavor that even those who haven’t tasted yuzushu will fall in love with them.

The new KitKats went on sale at souvenir stores around the country on September 5, and as they aren’t a seasonal or limited-edition variety, each nine-piece box will be available to purchase year-round at a retail price of 700 yen (US$6.50).

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