Rinse the sushi rice under cold water until the water runs clear.
Combine the rinsed rice and water in a rice cooker and let it soak for 30 minutes.
Cook the rice according to the rice cooker instructions.
Once cooked, let the rice sit for 10 minutes before transferring it to a bowl.
Mix rice vinegar, sugar, and salt in a small bowl until dissolved.
Pour the vinegar mixture over the cooked rice and gently fold it in.
Allow the rice to cool to a manageable temperature.
Wet your hands with water to prevent sticking.
Take a handful of rice, flatten it in your palm, and place your filling in the center.
Mold the rice around the filling into a triangle shape and wrap with a strip of nori.