Rinse the sushi rice under cold water until the water runs clear.
Combine the rice and water in a rice cooker and cook according to the manufacturer's instructions.
Once cooked, transfer the rice to a bowl and let it cool slightly.
In a small bowl, mix rice vinegar, sugar, and salt until dissolved.
Pour the vinegar mixture over the rice and gently fold to combine.
Slice the salmon and tuna into thin, bite-sized pieces.
Prepare the avocado and cucumber by slicing them appropriately.
In serving bowls, layer the sushi rice as the base.
Artfully arrange the fish, avocado, and cucumber on top of the rice.
Garnish with pickled ginger, wasabi, and sesame seeds.