I’m sitting with Frankie Olivieri Jr. outside his restaurant, Pat’s King of Steaks, a South Philadelphia institution that pumps out the city’s famously messy sandwich 24 hours a day. It’s 10 a.m. and the cherry-red picnic tables are mostly empty; I’m here during the lull between workers coming off the night shift and the crush of afternoon tour buses that precedes late-night revelers.

The cheesesteak I smell frying is nearly the same as the original born here 85 years ago: An Italian hoagie roll packed with thinly sliced rib eye and Spanish onions, both sautéed on a flat-top grill, sometimes with peppers and mushrooms. Cheese, whether you opt for provolone or the iconic Cheez Whiz—just “Whiz” in local parlance—holds the whole thing together.

But ask anyone what really makes a cheesesteak and they’ll tell you it’s the roll. A descendant of an old-world Italian bread, the chewy, slightly crusty hoagie roll (Olivieri swears by New Jersey–based Aversa’s Bakery) is the perfect vehicle for dripping meat.

An informal Yelp census puts the number of cheesesteak spots in the city at 96, but the sandwich is served everywhere, from delis to high-end restaurants. And, while the basics (meat, onions, roll) don’t vary much from place to place, arguing about which is best—and whether sliced beef is better than chopped—is a pastime on par with running the Rocky steps or dissecting the latest Eagles game.

“You’re always hearing about how one particular cheesesteak place is the best, even though I probably make more in one day than they sell in a year,” says Olivieri. “But cheesesteak joints are like opinions. They’re everywhere, and all valid.”

Only Pat’s can claim to be the original. The cheesesteak, Olivieri tells me, was invented in 1930 on this very corner by his grandfather Harry and his great-uncle Pat Olivieri. The duo worked as hot dog vendors in an open-air Italian market, and when times were good they would buy beef and fry it up with onions for their lunch. One day, a taxi driver asked if he could buy the sandwich instead of a hot dog. Pat offered to split it. The driver, smitten, advised the pair to sell them.

It wasn’t until World War II, however, that the cheesesteak became a Philly emblem. A true showman, Pat started a rumor in the days of WWII rationing that his sandwiches contained horse meat, then, in mock outrage, offered a $10,000 reward for someone to prove it. Business boomed and competitors followed.While places like Pat’s continue to churn out the classics, the current cheesesteak scene reflects the city’s changing dining landscape. HipCityVeg makes a respectable vegan version. The cheesesteak even gets an haute touch at Barclay Prime, a swanky steak house, where Wagyu beef is tucked into a sesame roll and piled with foie gras and truffled cheese. Paired with a half bottle of Perrier-Jouët Grand Brut, it’ll set you back a cool $120.

“Why mess with tradition?” I ask Mark Twersky, Barclay’s executive chef, later that day. “Cheesesteaks are fun to play with,” he replies. Though purists may quibble with his methods, he grew up with the sandwich—he’s partial to Geno’s, a Pat’s rival, or Jim’s, an old-school spot—and understands its vital role.

“After dinner at a great new restaurant—even if it’s ours—you’re still going to go out and get a cheesesteak at two in the morning,” he says. “Because that’s what you do in Philadelphia.”

Ready to indulge? Visit these spots for the best cheesesteaks in Philadelphia.

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