When Hiroe Tanaka started her business, she was a college dropout working for a bankrupt restaurant business.  All she had was a handwritten recipe from her recently-deceased father.

Nine years later, that simple handwritten recipe for her father’s special kushikatsu — Japanese deep-fried meat and vegetable skewers that were popularized as street food — has made Tanaka a millionaire many times over.

Kushikatsu was Tanaka’s father’s signature recipe, even when she was a child. He reportedly went to great lengths to make sure that the oil, batter, and sauce were all exactly right. When Tanaka was 21, her father died and she took on a variety of jobs, eventually settling with working for Keiji Nuki, whose restaurant business was struggling, according to Bloomberg.

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When the global recession hit in 2008, Nuki was about to close up shop when Tanaka finally — after years of searching — found her father’s recipe for kushikatsu in a box of memos and notes that he left her before he passed away.

Together, Nuki and Tanaka opened up shop on a tiny property. Much to their surprise, the kushikatsu went viral and people were lined up around the block at all hours of the day and night.

That handwritten recipe elevated Tanaka from a part-time employee to vice president of the now-$82 million Kushikatsu Tanaka Co., which has 146 locations across Japan-- and one in Hawaii. Kushikatsu Tanaka announced an IPO in September, and shares have since gained 50 percent in Japan’s markets.

“I pay tribute to my father every day,” Tanaka told Bloomberg. “It all happened because of the recipe.”

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