Cook sushi rice according to package instructions. Mix with rice vinegar and let it cool slightly.
Cut sushi-grade salmon into bite-sized cubes and place in a bowl. Add soy sauce and sesame oil, then gently mix.
Slice avocado, dice cucumber, shred carrots, and chop green onions.
In a small bowl, mix soy sauce, sesame oil, and optional sriracha mayo until smooth.
Divide rice into bowls. Add salmon on top, then arrange toppings around it.
Drizzle sauce over the bowl and sprinkle sesame seeds before serving.
