Before Ken Rosenthal opened the bakery-cafe that would become Panera Bread, he was a businessman who didn’t know how to cook eggs.

“Everybody who had been in the bakery business and even some of his partners later on told him he was crazy,” his wife, Linda “Laya” Rosenthal told The Denver Post on Wednesday.

“I told him, ‘We have nothing. If we lose everything, we still have nothing,’” she said, laughing.

But Ken Rosenthal didn’t lose everything — he opened the St. Louis Bread Company in 1987 in Kirkwood, Missouri, which would eventually grow into Panera Bread, a fast-casual eatery with more than 2,000 locations across the United States, including 37 in Colorado.

He remained involved in the company for more than 30 years.

Rosenthal died at his Scottsdale, Arizona, home on Friday from Alzheimer’s disease. He was 81 years old.

Rosenthal’s love for bread started in the 1980s, when his brother, Don Rosenthal, told him about a bustling bakery-cafe, Le Boulanger, that shared a building with his office in San Francisco.

He temporarily moved to California and learned to bake from owner-manager Roger Brunello, who carried a sourdough starter on the plane with him to St. Louis before Ken Rosenthal opened his first store.

While some people were surprised and skeptical about an entrepreneur opening a bakery, his family wasn’t.

“He put his heart and soul into it and he loved it,” Laya Rosenthal said. “He believed in it, and I believed in him.”

Despite opening on the day of the 1987 Black Monday stock market crash, the St. Louis Bread Company grew to 18 locations by the time Ken Rosenthal and his business partners sold it to Au Bon Pain in 1993.

“What we were doing at the time in St. Louis, there was no competition,” Rosenthal’s longtime friend and business partner Doron Berger said. “That was part of the genius of Ken, because everyone tried to talk him out of doing it before he opened the first location, but nevertheless he pursued it.”

Rosenthal consulted for the company for a few years before starting a franchise operation, Breads of the World, which would go on to open nearly 100 Panera stores in Colorado and Ohio, Berger said. Rosenthal remained active with the franchisee until it was sold in 2018.

He and his wife moved to Cherry Creek in 2002 to be closer to their children and grandchildren and continue running Breads of the World, later moving to Greenwood Village.

No matter what role he held in business, Rosenthal’s humility, generosity and kindness remained constant, according to his friends and family.

While he wasn’t one to talk about his own success, Rosenthal’s son-in-law Craig Flom remembers walking down the hall with him before a corporate Panera meeting and seeing people staring and whispering as they passed by, with some walking up to him to thank him.

“Just watching their eyes when they talked to him — it was amazing and something I took away from it was his impact on so many people,” Flom said.

Rosenthal was born in St. Louis, Missouri, on April 11, 1943, to Adis and Herman Rosenthal. He attended University High School before jumping into business, starting multiple ventures before turning to the culinary world.

He is survived by his wife of 55 years, Laya Rosenthal; four children; 13 grandchildren and his brother.

Services were held Monday at Aish of the Rockies in Greenwood Village, Colorado.