More than a century ago, tempura was just a common street food in Japan that came with a thick crust and was wrapped with paper. The man who elevated this snack to another level was Asano's grandfather Kikutaro Asano who founded the legendary tempura restaurant Inagiku in Asakusa, Tokyo in 1904.

Asano says that his grandfather was a man who never compromised on his exacting standards. He recalls how every customer was only allowed one bottle of beer. Those who asked for more were sternly told: "This is a tempura restaurant, not a bar."

Asano's father Nobuo was known for creating a special sesame oil in the 1960s that accentuated the taste of the tempura. He did this by toasting sesame seeds for a shorter period, which resulted in the oil being lighter in color than the ones commonly used to cook tempura.