In this episode of How I Built This, Guy Raz interviews Bill and Leigh Keith, the brother-sister co-founders of Perfect Snacks. They recount their unconventional upbringing, raised in poverty while traveling the Western United States in a school bus with their ten siblings, and how their father, a health and fitness enthusiast, inspired them to create the original Perfect Bar recipe. The interview covers their early struggles selling the bars door-to-door, the challenges of scaling the business, a near-disastrous salmonella scare, securing investment, and eventually selling a majority stake to Mondelēz. They also discuss the family dynamics of working together, the importance of their mother's support, and how they navigated the transition to new leadership after the acquisition.