A sensation in Japan, the green-tea version of the chocolate bar is finally reaching British supermarkets – but when will edamame and sweet potato KitKats arrive on our shores?

The chocolate coating is an Instagrammable – if lurid – lime green, with the promise of a “sweet and fragrant” flavour. Fifteen years after it went on sale in Japan to squeals of acclaim, the matcha green tea KitKat will hit UK supermarket shelves from this month as its manufacturer, Nestlé, brings the cult snack to a wider European audience – albeit with its flavour modified for our less-refined tastebuds.

The matcha white chocolate four-finger bar is the most popular flavour of the mindboggling 350-plus KitKat varieties – including cherry blossom, edamame bean and sweet potato – which have been developed for the Japanese market. There, KitKat has become a household name, popular as a gift and with tourists keen to bring home a souvenir. Some are sold exclusively through airport shops, with limited-edition flavours often sparking an internet frenzy.

It is hard to imagine the Britain of 1935, when the KitKat was born (then called Chocolate Crisp), taking to the subtle flavour kick of matcha. But the powdered green tea has gone from niche Japanese speciality enjoyed at traditional tea ceremonies to one of the UK’s most popular flavours. Selfridges says it is one of the bestsellers on its grocery aisle, with sales up nearly 80% year on year. “Matcha is used as an ingredient in products across many of our ranges from chocolate, macarons and biscuits to coffee, nuts and cold drinks,” says Anna Burleigh, a buyer at the store. “The unique flavour and reported health benefits have created a loyal customer who seeks out these products.”

While most people won’t be doing their weekly shop at the London department store, the matcha latte is now a staple at most high-street coffee chains. Smoothies and ice-creams have also flooded the market.

The matcha KitKat follows the equally photogenic but perhaps less flavoursome pink chocolate KitKat Ruby in the UK (which one Guardian journalist described as tasting like a “four-finger bar of soap”) in 2018. For Easter this year comes the KitKat Ruby Easter Egg. Cameras at the ready.