Mark Zuckerberg hits the 'like' button at Pat's Steaks

And just like that, Mark Zuckerberg has inserted himself into an age-old Philadelphia food debate.

The Facebook founder posted Sunday night a photo of his gray-T-shirted self at the window of Pat's King of Steaks in South Philadelphia, with the caption, "Traveled all the way to Philadelphia for the best cheesesteak in the land."

Night manager Mikey Boninfante told The Inquirer that the tech billionaire and a small entourage emerged from a black limo at the 24-hour institution at Ninth and Passyunk, where the sandwich was invented eight decades ago.

Zuckerberg, 33, waited in line and ordered six steaks with Cheez Whiz and fried onions — using the correct terminology of "Whiz wit'," no less — paying $66 cash.

"He said he's a cheesesteak fanatic and is in town, trying all the spots," Boninfante said, adding that Zuckerberg had told him he was here on business.

After the crew ate the sandwiches outside, Boninfante said, Zuckerberg returned to the window to shake hands with Pat's staff. "He was over the moon," he said.

At which point, Boninfante asked if Zuckerberg wanted a receipt for tax purposes.

Fuggedaboutit.

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