For years McDonald's customers have wondered what ingredients make the Big Mac Special Sauce so good. That question will not be answered, however the highest lucky bidder on eBay will get a bottle shipped to them.

An eBay seller is offering up a bottle of McDonald's Special Sauce labeled as Bottle #1 of 200. On eBay Australia, 135 people have already bid on the sauce and the current selling price is $23,100 Australian dollars, about $17,867 U.S. dollars according to LikeForex.com's currency converter.

The auction still has over seven days left before bidding will close. The price could continue to rise in those next seven days.

The best part of the auction is the proceeds from the auction will go to the Ronald McDonald House Charities.

The eBay description for the 500 mL bottle of Special Sauce describes the sauce in quite a humorous way.

So slide the mustard, mayo and tomato sauce to the back of the fridge -- because everything tastes better when it tastes like the Big Mac.

Ebay requires bidders to be pre-approved to place a bid on this special auction and has a link to get registered prior to bidding.

From the listing, it appears that only bidders in Australia will be able to bid on this and have it shipped to their residences. The bottle will ship free. The listing says the sauce is best before May 23.

According to the listing, Big Mac Special Sauce makes everything taste better:

"Leftovers... better!
Steak... better!
Your mum's amazing lasagne... better!
Your boyfriend's gross lasagne... better!
Chicken Caesar Salad... better!
Hungarian Goulash... better!"

The seller, bid_for_good, has 100 percent positive feedback and offers up other items for sale with proceeds going to various charities. The seller is offering free shipping on this item.

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