The Shamrock Shake Is Officially Back on the McDonald's Menu

But hurry, it's only around for a limited time.

We know that old song says that Christmas is "the most wonderful time of the year," but Shamrock Shake season has to be a close second. Yes, everyone, the pastel-hued beverage is back on McDonald's menus everywhere.

According to the fast food giant, the shake was created in 1967 by Hal Rosen, a Connecticut McDonald’s owner and operator. It debuted nationally in 1970 and was an instant success across the country.

The frozen treat made its annual debut on Monday, February 20, and will be available at participating restaurants nationwide for a limited time. (McDonald's hasn't said exactly how long "a limited time" lasts, but it will likely stick around through St. Patrick's Day.)

For those who have somehow made it to 2023 without ordering one, the seasonal shake involves blending vanilla soft serve with minty Shamrock Shake syrup and a whipped cream topper. In 2020, McDonald's doubled its Shamrock offerings by adding an Oreo Shamrock McFlurry, and that mint cookie dessert is also available for a limited time.

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And although the Shamrock Shake has been available at McD's throughout the country for decades, it has been connected to Philadelphia — and to the origin of the Ronald McDonald House — since 1974.

Then Philadelphia Eagles general manager Jimmy Murray made a donation to the Children's Hospital of Philadelphia, which was in desperate need of renovations and upgrades at the time. According to Billy Penn, after making his initial donation, an oncologist told Murray that the hospital also really needed a place where parents and families could stay while their children were receiving treatment.

Murray reached out to a friend at a local ad agency — which just happened to be working with McDonald's to promote that year's Shamrock Shake — and said he'd love it if 25 cents from the sale of each Shake could go toward purchasing a building near the hospital for families to use.

The agency contacted McDonald's regional manager Ed Rensi, who agreed to the plan — but also asked if McDonald's donated that much money, could the new building have the name the Ronald McDonald House? As Billy Penn reported, "Murray said that if they gave all the proceeds over, McDonald's could name it the Hamburglar House for all he cared."

What started with a quarter-a-shake idea has grown to more than 270 chapters, which include the Ronald McDonald House, the Ronald McDonald Family Room, and the Ronald McDonald Care Mobile, in more than 60 countries.

Enjoy your Shamrock Shake while you can — the most wonderful time of the year never lasts long.