Kat Cole was a teenager when she started working at Hooters, and her work ethic combined with the company's sprawling empire propelled Cole to multiple countries and management roles. Cole, who parlayed that experience into business school and taking over the Cinnabon brand, says she's never forgotten her roots or the value of hard work. "I was always trying to prove I wasn't defined by where I came from," she said. "That was the driving force." Cole recently earned a spot on Fortune's 40 Under 40 list of executives.