Rinse rice in a strainer under cold water until water runs clear. Transfer rice to a medium saucepan, add 3 cups water, and bring to a boil. Reduce heat to low, cover, and cook until rice is tender and water is absorbed, about 20 minutes.

Meanwhile, combine rice wine vinegar, sugar, and sake in a microwave-safe bowl. Microwave on high until sugar is completely dissolved, about 1 minute.

Place cooked rice in a large bowl. Stir in vinegar mixture until well combined and let sit for 2 minutes. Stir again.