Mr. Rensi began at McDonald's as a grillman in Columbus, Ohio, in 1966, when he was 22 years old. After opening the first Ronald McDonald House (a home away from home for families of hospitalized children) in 1974 and developing Chicken McNuggets in 1983, he became CEO of McDonald's USA in 1991. He retired from the Oak Brook-based burger chain in 1997 at age 53. Mr. Rensi, who joined the Famous Dave's board in January, hasn't actually retired, however. In 2010, he launched America's Better Burger LLC, whose Tom & Eddie's chain has three locations in suburban Chicago. Mr. Rensi, former chief executive of McDonald's Corp.'s U.S. operations, developer of Chicken McNuggets and founder of the first Ronald McDonald House, was named CEO in May of Famous Dave's of America Inc., a 194-unit barbecue chain based in Minnetonka, Minnesota. His goal is to revitalize what he calls “a legacy brand with an enormous following.” The 70-year-old is giving himself five years to do it.