Place the rice in a fine mesh strainer or colander and rinse it under cold running water, stirring gently with your fingers or a spoon. Continue rinsing until the water runs clear, indicating that most of the starch has been removed. (Rinsing helps remove excess starch from the surface of the rice grains, which can result in a cleaner, fluffier texture once cooked. Some sushi rice brands are pre-rinsed or partially rinsed, so check the package for instructions.)

In a large saucepan, bring the water to a boil. Stir in the rinsed rice, then reduce the heat to low. Cover the saucepan and simmer for 20 minutes, or until the rice is cooked and the water is absorbed. Remove from the heat and let the rice steam, covered, for 10 minutes to firm up and absorb any excess moisture.

While the rice cooks, in a small bowl, whisk together the rice vinegar, sugar, and salt until the sugar and salt are fully dissolved.

After the resting period, gently fold the vinegar mixture into the cooked rice until evenly distributed. Be careful not to mash the rice; you want to maintain its fluffy texture.