Updated July 23, 2022 at 7:07 AM ET

Chicago is rich with iconic foods.

There's the classic Chicago hot dog, with just about everything on it EXCEPT ketchup. There's deep dish pizza. There's barbeque, flaming saganaki, chicken Vesuvio, and cheese and caramel popcorn.

And, of course, there's the Italian beef sandwich.

A new FX series called The Bear has shone a spotlight on the dish. The show is about a fine dining chef who returns home to Chicago to manage his family's Italian beef shop.

Like any great series, there's the drama, comedy and pathos — but there's also the food: thinly sliced beef, sweet peppers, a pickled vegetable relish called Giardiniera, all stuffed into an Italian loaf and topped au jus.

The sandwich started with cheaper cuts

The story of how the Italian beef sandwich came to be one of Chicago's signature foods begins with discrimination against Italian immigrants in the early 20th century.

When those families would go to market, they would be only be sold the cheaper cuts of meat, like the roast or the ends of the cow, which are less tender, says Chicago historian Shermann "Dilla" Thomas.

But three steps helped transform a tough cut of meat into a prime sandwich to feed big families.

The families found they could tenderize the meat by cooking it for a long time, like over the course of a workday, Thomas says. They also masked the quality of the meat with fresh bread. And they sliced the meat very thin, to help stretch the supply.

The sandwiches were frequent guests at weddings, where families would gather at a banquet hall or a home and bring dishes after the ceremonies.

Historians largely believe Al's was the first shop to sell the sandwich, starting in the 1930s. The shop is still a mainstay in Chicago's Little Italy neighborhood, and others soon followed around the city.

Italian beef becomes a TV star

One of those shops, Mr. Beef on Orleans, opened in 1979.

Situated in the River North neighborhood, it was in the shadow of factories, says founder and owner Joseph Zucchero. Now, River North is a trendy neighborhood, and patrons still frequent the little shop.

One longtime patron is Chris Storer, a friend of Zucchero's son — and the creator of The Bear.

To create the show's Italian beef shop, The Original Beef of Chicagoland, Storer turned to Mr. Beef on Orleans as inspiration.

FX shot scenes inside and outside the restaurant, and they created a replica of the kitchen in Cinespace, a movie studio on Chicago's West Side.

"They wanted me to see it, and my mouth dropped. I was like, 'Oh my God.' I mean, from the floor to the ceiling to the countertops to the equipment," Zucchero says, "you actually walked inside [Cinespace] and walked into Mr. Beef."

Now, business has picked up for Mr. Beef, and Zucchero attributes that to the series.

It's a relief for the restaurant, which saw lower sales during the pandemic as fewer workers commuted to the downtown Loop area adjacent to River North.

It's also good news for Italian beef lovers like the Chicago historian Dilla Thomas, who described his regular order: lightly dipped to avoid soggy bread, both hot and mild peppers, and a little bit of mustard.

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