Tuna Mayo Onigiri is a popular variation of Onigiri that combines the flavors of canned tuna and mayonnaise. To make Tuna Mayo Onigiri, start by preparing the sushi rice as mentioned in the Classic Onigiri recipe. Once the rice is ready, mix canned tuna with mayonnaise in a bowl. Take a small handful of rice and shape it into a triangle or oval shape. Make an indentation in the center and fill it with the tuna mayo mixture. Close the rice ball and wrap it with a strip of nori seaweed. Tuna Mayo Onigiri is a delicious and satisfying snack that can be enjoyed on its own or as part of a Japanese-style lunch. The combination of the creamy tuna mayo filling and the sticky rice is sure to please your taste buds.