Onigiri

O-nigiri ( or ; おにぎり^?), also known as o-musubi (お結び; おむすび^?), nigirimeshi (握り飯; にぎりめし^?) or rice ball, is a Japanese food made from white rice formed into triangular or cylindrical shapes and often wrapped in nori (seaweed). Traditionally, an onigiri is filled with pickled ume (umeboshi), salted salmon, katsuobushi, kombu, tarako, or any other salty or sour ingredient as a natural preservative. Because of the popularity of onigiri in Japan, most convenience stores stock their onigiri with various fillings and flavors. There are even specialized shops which only sell onigiri to take out. Due to the popularity of this trend in Japan, selling onigiri in small shops has spread to other parts of the world, such as Taiwan, China, Hong Kong, South Korea, Thailand, Switzerland, Hawaii, New York City, London, Australia, Canada, Brazil, and parts of California.

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Wikipedia