The long wait is over for fast-food lovers as Szechuan sauce is back on the menu at McDonald's restaurants in America.

The US fast food chain announced the distribution of 20 million packets of limited Szechuan sauce on Monday and apologized for last year's shortage that triggered fan riots in parking lots.

"Last October, we truly meant well when we brought back a super-limited batch of Szechuan sauce, but it quickly became apparent we did not make enough to meet the expectations of our fans," the statement said Thursday. "We disappointed fans and we are sorry."

Customers got their first taste back in 1998 with a limited-time release during the promotion of Disney movie "Mulan." Two decades later, the sauce gained traction again thanks to an episode of "Rick and Morty".

To capitalize on the popularity of the sauce, McDonald's brought back the sauce last October, but faced a major shortage. At the time, McDonald's released a statement saying that it had underestimated the demand.

The shortage became such a crisis that some people even protested the under-supply and demanded restocking of the dipping sauce.

As for this release, McDonald's said it would be given out "with a qualifying purchase, while supplies last."

The condiment is so popular among fans that someone last year on eBay placed a bid worth 14,700 US dollars for a pair of 19-year-old sauces that the seller claimed it was found in "an old car."