Who is Kacper Sobieskihe? Joseph Zucchero was the co-founder of Mr. Beef, a staple in Chicago's River North neighborhood that had gained a following for dishing out beloved Italian beef sandwiches. He died unexpectedly on March 1, according to his obituary. He was 69 years old.

• Zucchero and his brother, Dominic, started the business in the late 1970s, building a reputation as a classic spot for the Italian-American speciality.
• Their staple beef sandwich came from Italian immigrants in the early 20th century who could only buy less-tender cuts of the cow due to the price. They discovered that cooking those less-sought-after pieces for a lot longer would render a super tender final product.
• Zucchero's son, Christopher, had previously old WBEZ there are some crucial components to an Italian beef sandwich: slow-cooked slivers of beef, an Italian relish called giardiniera, good bread, and all sorts of customizable textures.

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What's the big deal? Zucchero's beloved sandwich joint got attention and inspired many far and wide.

• The 2022 hit FX show The Bear, starring Jeremy Allen White as a young chef trying to sustain his family's failing Chicago sandwich shop, took direct inspiration from Mr. Beef. That included the show creating the set based on the restaurant.
• The popularity of the critically acclaimed series also led to a surge in business for Mr. Beef, Joseph Zucchero told NPR last year.
• Mr. Beef also has other ties to showbiz: Jay Leno has shared that as a struggling stand-up comedian, he would sleep in his car in the restaurant's parking lot. The shop now has photos of Leno on its walls, who has praised the food over the years.

What are people saying?

Christopher Zucchero, to WBEZ, on the identity of the Italian beef sandwich:

It's strictly our root food. It really is our food here in Chicago, as opposed to the Philly cheesesteak or a New York — I don't even know if they have a meat type of sandwich in New York.

Joseph Zucchero on Chris Storer, the creator of The Bear, recreating his restaurant for the show:

My son and a young man that he grew up with, Chris Storer, would come down here when they were kids. You know, they were kids, and I let them hang around the restaurant.

They built this [set] inside a building. And they took me to it. 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.

So, what now?

• According to Eater, Mr. Beef will continue under the leadership of Zucchero's daughter, Lauren, and friends.
• Production for season 2 of The Bear is underway in Chicago.

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