Only 300 of these exclusive jars will be available to customers.

Over the years, McDonald’s has brought out some amazing burgers and limited edition releases in Japan. For many, though, it’s the fast food chain’s star staple, the Big Mac, that stands out above the rest, with its delicious and famously distinctive sauce.

Now, for the first time, Japanese customers will be able to enjoy the sauce in all its glory, without any extra trappings like meat or buns. What’s more, it comes in an adorable 220-gram (7.8-ounce) jar inside packaging that resembles an authentic Big Mac box.

Inside the box, like a gleaming golden McNugget, is the coveted burger ingredient that’s proving to be nearly as valuable as gold itself. When the first bottle of Big Mac Special Sauce was given away in the U.S. earlier this year, the product immediately began appearing on online auction sites like Ebay, where the going rate was US$100 each.

While the U.S. release was limited to 10,000 units, in Japan, only 300 will be made available. And they won’t be given away for free here; they’ll be sold for 1,900 yen (US$17.10) each.

The reason the jars of special sauce are being made available at all is to mark the opening of a new McDonald’s online store in Japan, which launched on global retailing site Rakuten on 31 May.

The store currently sells limited-edition items like McDonald’s-themed hats, bags and accessories, as part of a collaboration with Japanese clothing brand Beams. The only edible item at the store, though, is the Big Mac sauce, which can be purchased exclusively from this site for a limited time.

If you’d like to get your hands on one of these sought-after jars, be prepared to have your finger poised above the purchase button at the online store from 12:00 p.m. on 3 June. While the company states that the jars will be on sale from 3- 27 June, with only 300 available, stocks are likely to sell out within minutes of being released.

Source, images: Rakuten/BigSurprise