If it hasn’t already, allow your leftover Sushi Rice to cool before beginning. (If cooking Sushi Rice from scratch, follow the instructions on the box).
In a bowl combine cooked Sushi Rice with tuna fish, Original Mayo, and salt or Sushi Soy Sauce to taste. Using a fork, stir all ingredients together.
Using your hands, press the rice mixture to form your tuna rice balls.
In a separate shallow bowl add White and Black Sesame Seeds together, then roll each rice ball into the seeds. Transfer to a plate and serve immediately, or carefully seal and keep rice balls refrigerated for a maximum of 2 days.