When Hiroe Tanaka's father died, he left behind something that would change her life: a recipe for fried meat on a stick. It was an act of love. His daughter adored the Japanese street food known as kushikatsu, and he'd spent endless hours working out how to make it just right.

The handwritten memo, which detailed how to cook the seemingly simple dish, helped save a restaurant business from bankruptcy in 2008, elevated Tanaka from part-time employee to vice president of a company named after her, and made her a multimillionaire. The university dropout who once worked as an office lady now sets strategy for the $82 million Kushikatsu Tanaka Co.

"I pay tribute to my father every day," says Tanaka, 46. "It all happened because of the recipe."