Step 1

Gather all the ingredients. If you change the amount of rice, please read the post on rice to water ratio.

Step 2

Add water just enough until it submerges all the rice. Then discard the water immediately (so the rice doesn't absorb the cloudy water). Tip: Rice absorbs water very quickly when you start rinsing, so don't let the rice absorb the first few rounds of water.

Step 3

Use your fingers to gently wash the rice in a circular motion for 15-20 seconds.

Step 4

Add water and discard the water. Repeat this process a couple of times until the water is clear.

Step 5

When the water is almost clear, drain well. Tip: Use a fine-mesh sieve to drain for 5 minutes and shake off excess water.

Step 6

While draining the rice, wash the sweet potatoes with a brush under running water and cut them into ¾″ (2 cm) thick slices.

Step 7

Cut the sweet potato into ¾″ (2 cm) cubes. Soak in cold water until ready to use. Tip: This is an important step to remove astringency from the sweet potatoes and prevent from discoloration.

Step 8

Add the drained rice in the rice cooker bowl (or the donabe or heavy-bottomed pot). Add sake, mirin, and salt.

Step 9

Add measured water and mix all together with chopsticks.

Step 10

Drain the sweet potato well. Place the sweet potatoes on the rice in an even layer. DO NOT MIX with rice (Rice can't cook evenly when you mix with other ingredients). Let the rice soak for 20-30 minutes.

Step 11

Put the rice cooker bowl in the rice cooker and start cooking (if your rice cooker has the Mixed or Umami Mode, use it; otherwise use White Mode (or simply turn it "on").

Step 12

Cover the donabe (or heavy-bottomed pot) with the lid. Turn on the heat to medium-high and bring to a boil. This should take about 8-10 minutes, but it depends on how much rice and sweet potatoes are in the pot and the heat on the stove. Once boiling, reduce heat to medium low and cook for 13-15 minutes. Turn off the heat, remove from the stove, and let it rest, undisturbed, for 20 minutes.

Step 13

Add the black sesame seeds in a small pan and sauté until fragrant, about 2 minutes, over low heat (optional step). Combine the toasted sesame seeds and salt in a small container.

Step 14

Once the rice is ready, fluff the rice gently with a rice paddle. Serve into individual bowls and sprinkle some gomashio on top to enjoy!

Step 15

You can keep the leftovers in an airtight container and store in the refrigerator for up to 2 days or in the freezer for a month.