Onigiri

Onigiri , also known as omusubi or nigirimeshi (握り飯), is a Japanese rice ball made from white rice. It is usually formed into triangular or cylindrical shapes, and wrapped in nori (seaweed). While modern onigiri can be filled with a wide variety of ingredients, including both savory and sweet fillings, traditional fillings are often salty or sour, such as salted salmon, umeboshi, katsuobushi,... (Wikipedia)