The Okinawan Spam soul food sandwich that’s on a roll

The success of a Japanese man who took an onigiri (rice ball) sandwich — known for years as the soul food of Okinawa — and turned it into a booming franchise began when his wife cooked the pork and fried egg snack for him one morning at home.

Shortly after his culinary revelation about a decade ago, Katsuaki Kiyokawa, 53, started a restaurant specializing in the pork tamago (egg) onigiri sandwiches, and his chain, Potama Co., has since grown rapidly beyond Okinawa to urban centers such as Tokyo and Fukuoka, as well as overseas to Hawaii.

Rival shops have also sprung up to take advantage of the craze for the hot and fluffy treats, inspiring the food industry in Okinawa to try expanding the appeal of other local cuisines and specialties.