In Japan, some of the most prized types of sushi are loved by gourmets for their rich flavor. High-quality uni (sea urchin) is decadently creamy, and the premium cuts of tuna are those with extra fat.

But this chain of restaurants in Japan might be offering the richest sushi ever, since the pieces have a pat of butter on them!

Obviously, butter isn’t a traditional sushi ingredient, but the four-restaurant chain Jinen has decided to add unagi butter sushi to its menu. As promised, each piece is a morsel of vinegared rice topped with a slice of unagi (freshwater eel) and butter, with the whole thing tied together with nori seaweed.

While Japan is generally intrigued by the prospect of adding Japanese culinary influences to western cuisine, the country tends to be far less receptive to trying to spruce up traditional Japanese dishes with foreign flavors. Still, Jinen’s unagi butter sushi is a big hit with those who’ve tried it. Satisfied diners say it feels like its melting in your mouth, and one true believer exclaimed “I could eat this every day!”

It’s a little surprising to hear that sushi and butter is such a palate-pleasing pairing, but then again, sautéed fish is often cooked with butter or oil, so maybe the idea isn’t as crazy as it sounds. Unagi butter probably also owes some of its popularity to the fact that all of Jinen’s branches are in Osaka, a town that traditionally can’t say no to hearty flavors and tasty eats.

Who knows? Maybe we’ll see a piece of unagi butter floating down the river in Osaka the next time the city does one of its public art projects.

Related: Jinen location list
[ Read in Japanese ]