The Sweet Sauce Burger King Japan's New Fries Are Served With

Of all the traits that define a culture, you could argue that none is tastier than the sauce we choose to put on our fries. Americans prefer ketchup, the Brits reach for malt vinegar, French Canadians have their gravy, and the French in France dip fries in mayonnaise (via Atlas Obscura). In Japan, many restaurants opt to liven up fried potatoes with powdered spices. The fries and the powder are mixed together in a bag — for example, Japanese McDonald's Shake Shake Fries.

Burger King in Japan is upending just about everyone's expectations about how to give french fries a flavor boost. Starting October 22, BK Japan offers Clown's Sweet Fries: french fries with a light drizzle of "special MIX chocolate sauce," according to the chain's website. The product description noted that "the sweet and sour taste is addictive."

Burger King Japan sells Clown's Sweet Fries for 330 yen or about $2.90. Also, Burger King customers in Japan can upgrade their ordinary fry order to Clown's Sweet Fries for no extra charge. The chocolatey fries are offered for a limited time only, while supplies last.

BK Japan's website calls Clown's Sweet Fries, its latest limited-time-only side order, "sweet, salty, unstoppable deliciousness!" If you think you've never heard of combining french fries and chocolate before, then Business Insider would like to remind you that Wendy's customers love dipping their fries in their chocolate Frosty. After all, sweet and salty go together like chocolate and peanut butter, as a certain Mr. Reese would have been happy to tell you (via Hersheyland.com).

French fries and chocolate shouldn't sound unusual, especially to those with American palettes. Atlas Obscura says the French like mayonnaise for the way it accents the potato's flavor, and the British use acidic vinegar to balance the oil in the fries. America's ketchup is acidic, too, but it's also by far the sweetest dip of any mentioned here (with the possible exception of BK Japan's new Clown's Sweet Fries chocolate sauce). Ketchup has four grams of sugar per tablespoon, which is twice the sugar content of a Frosty, per Wendy's website. (One 12-ounce Frosty — 24 tablespoons — has 47 grams of sugar.) So if you want to go light on the sugar, take ketchup out of your french fry equation and substitute it with ... just about anything else.