Begin by rinsing the rice under cold water. The best way to do this is by using a rice washing bowl or a colander that is made for small grains.
My sister, the recipe creator, uses a rice steamer to cook her sushi rice, and she suggests using short or medium-grain rice. Add 2.5 cups rice and 2.25 cups water to your rice steamer and press the ‘cook’ button or the applicable button for your model. Below, in the NOTES section, are the cooking methods using a rice steamer, Instant Pot, and stovetop.
Whichever cooking method you use, be ready to transfer the cooked rice to a cooling pan as soon as it is done. If you are using a rice steamer, as soon as the cooker beeps, immediately transfer the rice to a cooling pan which can be as simple as a baking sheet. Be sure to have hot pads ready and be mindful of the steam.
While the rice cooks, go ahead and make the rice seasoning with rice vinegar, sweetener, and salt. Mix the ingredients together in a saucepan and heat on medium-high. Watch carefully, and turn the heat off when it begins to simmer. You don’t want this mixture to come to a boil.
When the rice has finished cooking, immediately dump it onto a baking sheet and pour the vinegar mixture over the top. Mix gently and begin spreading the rice out evenly.
Spreading it thinly will aid in cooling it more quickly. When you stir and spread the rice, do it gently so that the rice does not become mushy. I like to draw thin lines, with my rice paddle flipped on its side, down the length of the pan using a dragging motion to accomplish this.
Once the rice is coated with the mixture and cooling, the fun begins! In Japan, they often set the pan under a ceiling fan or make it a group event and use paper fans or a piece of cardboard to fan and aid in cooling the rice down quickly.