Before You Start: For the steamed rice, please note that ¾ cup (150 g, 1 rice cooker cup) of uncooked Japanese short-grain rice yields 2¼ US cups (330 g) of cooked white rice. See how to cook short-grain rice with a rice cooker, pot over the stove, Instant Pot, or donabe. Now, gather all the ingredients.
In a large pot (I used a donabe), add 3 cups dashi (Japanese soup stock). You can make Awase Dashi or Vegan Dashi from scratch or use a dashi packet, as I demonstrate here. First, add 3 cups water and 1 dashi packet to the donabe.
Cover the lid and slowly bring the water to a boil on low heat. After a few minutes, open the lid and shake the bag to release more flavor.
Close the lid and continue to heat the broth. Once boiling, cook for 3 minutes and discard the dashi packet. Keep the lid closed and set aside.
Remove the excess fat from 6 oz boneless, skinless chicken thighs and cut the meat into small, bite-sized pieces.
Discard the tough stems of 2 shiitake mushrooms and thinly slice the caps.
Cut 1 inch carrot into quarters lengthwise and thinly slice them crosswise.
Slice 2 green onions/scallions into thin rounds and put them in a small bowl. Set aside for garnish.
Measure 1½ cups cooked Japanese short-grain rice. If you’re using cold pre-cooked rice, put it in a fine-mesh sieve and rinse under running water to remove any excess starch. Shake and drain well. If you’re using freshly made rice, you can skip rinsing.
To the hot dashi broth, add the chicken.
Close the lid and bring it to a boil on medium-low heat. Once boiling, use a fine-mesh skimmer to skim the scum and foam on the surface.
Add the carrot and cook covered until tender, about 4–5 minutes.
Once the carrot is tender, add 2 tsp usukuchi (light-colored) soy sauce and ½ tsp Diamond Crystal kosher salt to the broth.
Add the shiitake mushrooms and well-drained cooked rice. Cover to cook for 10 minutes.
Beat 1 large egg (50 g each w/o shell) in a bowl or a measuring cup with a pouring spout.
To create fluffy egg ribbons, slowly drizzle a thin stream of the beaten egg over the soup surface in a circular pattern, starting from the center and spiraling outward. For better control, place your cooking chopstick vertically at the edge where you pour the egg. Avoid pouring the egg in the same place.
Add some of the green onion and ½ tsp toasted white sesame seeds. Sprinkle ⅛ tsp white pepper powder at the end.
Cover with the lid and bring the pot to the table to serve in individual bowls. Enjoy!