Place rice in a fine mesh strainer, then run under cool water to thoroughly rinse. At first water will look murky or cloudy, but after 1-2 minutes, water will run clear.
Transfer rinsed rice to the bowl of a rice cooker, then fill to just under designated line with water. Cook rice according to machine instructions.
In a small sauce pan, combine rice vinegar, sugar, and kosher salt. Bring to a simmer over medium-high heat.
Transfer cooked rice into a large mixing bowl, then pour sushi vinegar on top. Use a rice spoon or spatula to gently toss the rice with vinegar, being careful not to squish the rice.
– Sushi rice will keep in an airtight storage container in a refrigerator for up to 3 days.