CHICAGO — The founder of the Chicago Italian beef shop that inspired FX’s “The Bear,” Joseph Zucchero, has died at 69, his son said.

Mr. Beef, the no-frills sandwich joint in Chicago’s River North, has been a neighborhood staple for decades. But it became a national sensation after it was portrayed by the gritty, fast-paced show released in June 2022.

 Joseph Zucchero Christopher Zucchero via AP

Zucchero died unexpectedly on March 1 at Rush Medical Center while undergoing treatment for cancer, said his son, Christopher Zucchero, who is a co-owner of the restaurant. “He was supposed to come home,” he said.

Zucchero said the family is waiting to learn exact cause of his father’s death.

“He was a magnificent human being. He was charismatic. He loved his restaurant. … He loved his family, his children,” Zucchero said.

Nothing will be the same at Mr. Beef without his father, Zucchero said.

“There’s going to be a huge … void here,” he said. “I’m in shock. … We act as if he’s still here. That’s kind of how we’re going to maintain and persevere, is to act as if he’s going to come around the corner.”

Mr. Beef’s doors stayed open after the elder Zucchero’s unexpected passing, his son said.

“We didn’t take any time off” — which is what his dad would have wanted. For 44 years, “Mr. Beef was always open the hours it said it was open,” Zucchero said.

The only exceptions: when “The Bear” was shooting, and this Saturday, when his father’s burial and services will be held.

“He was a tough human being. He was tough, but he was also fair. He loved everyone,” Zucchero said.

The Italian beef legend was “elated” when Christopher Storer, creator of “The Bear” and a childhood friend of Christopher Zucchero, centered the show on his shop.

“He was very proud of that,” his son said.