A 500ml bottle of McDonald's fabled Big Mac sauce has reached $17,640 in an eBay charity sale that closes on February 11. 

The sauce has never been made available outside the company's restaurants, despite its enormous popularity. 

Big Mac sauce has never been available on the market before

The company comments: "This bottle is #1 of only 200 being produced worldwide, and they won't be sold in restaurants. That makes it rarer than a spot on Bondi beach on New Year's Day…

"With 500ml to play with, you'll have enough to impress your friends at dinner parties, cheat your way to cooking show fame, and get elected as Prime Minister!

"Best of all - 100% of the auction sale price will go to Ronald McDonald House Charities, so get bidding on a legendary sauce for a legendary cause."

The sauce, which was a closely guarded secret for many years, contains mayonnaise, pickle relish and mustard along with garlic, vinegar and seasoning. 

Mark Lollback, chief marketing officer for McDonald's Australia, commented: "We're excited to be auctioning off the first-ever bottle of Big Mac sauce for a cause we are passionate about.

"It's going to be interesting to see just how much people are prepared to pay for such a sought after commodity."

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