Remove the stems from the shiitake mushrooms and chop the stems finely. Cut the napa cabbage into bite-sized pieces and mince the green onion.

Dust the inner side of the shiitake mushroom caps with 1/2 tbsp potato starch.

In a bowl, mix the ground chicken, minced green onion, chopped shiitake stems, and the seasoning for the meat mixture until sticky. Divide into 4 portions and stuff each shiitake cap with the mixture, shaping it neatly.

Line a pot with napa cabbage, add the soup base ingredients, and heat over medium heat. Once boiling, place the stuffed shiitake mushrooms meat-side up on top, cover, and simmer on low heat for about 10 minutes.