In a small bowl, whisk together yum yum sauce ingredients.
In large bowls, assemble rice bowls.
Start with 1 cup of rice in each bowl.
Top each with ½ package of yellowfin tuna, carrots, cucumber, a quarter of an avocado, seaweed snack sheets, pickled ginger, and sesame seeds.
Drizzle with yum yum sauce.
Serve and enjoy!