Tom Grogan’s first job paid him just £30 ($40) a day lugging bricks and hauling cement on a Birmingham building site. His latest payday? A £400 million ($532 million) takeover deal for the UK arm of Wingstop—the American fried chicken chain with celebrity fans like Kylie Jenner—that he cofounded with Herman Sahota and Saul Lewin.

And it’s all thanks to a chance encounter that traces back to when he was just 18 and not sure what he really wanted to do with his life. Like many Gen Zers today, the millennial decided to skip university and try his hand at the trade industry when he turned 16 years old.

He had been working as a labourer on a building site for 2 years when he met a property developer. Like Grogan, he hadn’t gone to university either and made his way from the bottom to the top, so he began to mentor the teenager.

“You meet certain people in life that change the direction of it,” Grogan exclusively told Fortune, adding that the mentorship led to an internship at Dragon Den (the UK equivalent of Shark Tank) star James Caan’s private equity firm in central London.

“So I started to understand how deals were put together. I was surrounded by a number of entrepreneurs, and that really quickly drove my fire to do something more with my life.”

“That very quickly led me to wanting to leave the world of employment to start my own business in the world of residential development and property development,” he added. “Along that journey, you have to meet lots of people, pitch for money. So I sort of understood the fundraising process and having worked within the world of private equity, I understood business plans and presentations.”

His real estate career set the stage for everything that followed, including meeting Sahota and Lewin—the men who would eventually help him launch Wingstop UK. They met while working in real estate and property development, but they decided to chance their arm in fast food seven years ago.

The trio saw the U.S. cult following and wanted to bring it to London. The problem? Nobody believed in them.

It took one cold email and 50 no’s before a $532 million yes

Grogan first discovered Wingstop through a line in a Rick Ross track—the Grammy-nominated rapper was a franchisee in the U.S. and heavily promoted the brand through his music. Wanting in, he tried his luck sending a cold email to the parent company in Texas.

“That’s really how we discovered Wingstop,” Grogan says. “We Googled it, and back in September 2016, I sent a cold email to Wingstop HQ: ‘Hey, you’ve got no presence in Europe. We’d love to launch the brand in the UK.’ Honestly, my thought process was, I’ll figure it out afterwards. It was a punt.”

To his surprise, the U.S. team replied positively, and Grogan’s cofounders came on board to piece the deal together. “We managed to convince the US parent that one, we could raise the necessary capital, and two, we would assemble a team around us. Yes, we had no experience, but we had identified a market gap. No one in the UK food-and-beverage world was speaking authentically to younger consumers the way brands like Gymshark and Nando’s were,” he explains.

“We didn’t have to worry about product or even food at first. We later learned just how tough operations are in a restaurant business, but being naive allowed us to jump headfirst into the challenge with no preconceptions. That was a gift.”

But getting the go-ahead was just the first hurdle: What followed were months and months of rejection from 50 investors.

“Three young men with no experience in hospitality, ultimately trying to pitch a brand, that no one in Europe had really heard of at that time—that’s a huge red flag,” Grogan continued. “We had a lot of setbacks…We took a lot of no’s and we had a lot of stops and starts, but by the skin of our teeth, we managed to pull it off.”

One of the largest fast-food brand takeovers in Britain

In the end, it took nearly a year to get that yes. “If we’d have stopped a week earlier, we wouldn’t be sat here now,” he said adding that each rejection was a lesson. “Ultimately, by the 50th presentation, a lot of the concerns that early investors had raised had either been figured out or we had an answer for.”

By then, they’d managed to secure what is now the site for their flagship restaurant in London’s West End. “So it made it a bit more real for those later investors that came to speak to us,” Grogan adds. “We say amongst ourselves that the stars have aligned on this journey, and that was probably one of the first stars that did align for us.”

And the stars really did align for Grogan and the team. They built the UK Wingstop brand from scratch; following in the U.S. branches’ targeting of Gen Z and millennial consumers, using social media and the celebrities of the moment. Today, there are 57 Wingstop sites in the UK.

Nearly nine years after sending that first cold email, the trio sold a majority stake of Lemon Pepper Holdings (Wingtop UK’s parent company) to Californian private equity firm Sixth Street just before the New Year. Already, it has plans to expand to 200 UK sites in the next five years. The deal marked one of the largest takeovers of a restaurant brand in Britain.

And Grogan, a 35-year-old Brit with zero prior restaurant cashed in his share of a £400 million ($532 million) windfall.

Reflecting on his meteoric rise from construction sites, Grogan tells the next generation of aspiring entrepreneurs that real-world experience—not lectures—shapes success.

“Unless you want to be a doctor or a lawyer, university is a waste of time. The experiences that you can have within the world of business, or with a mentor, or by becoming street smart are far more valuable than a textbook.”

This millennial went from being a builder on $5 an hour to launching (and selling) Wingstop UK for $532 million—with zero restaurant experience