Spam musubi is a snack and lunch food composed of a slice of grilled Spam sandwiched either in between or on top of a block of rice, wrapped together with nori in the tradition of Japanese onigiri. Inexpensive and portable, Spam musubi is commonly found near cash registers in convenience stores or mom-and-pop shops all over Hawaii, the Marianas[citation needed], and Hawaiian Barbecue restaurants in the mainland United States. Musubi can be easily made with the right materials, and typically only uses spam, rice, some salt, nori, and shoyu (soy sauce). In Hawaii, musubi with spam from a can or homemade luncheon meat is eaten as a snack or served in formal restaurants.