Add the bok choy during the last 2 minutes of cooking, just until wilted and bright green.
Add the sliced shiitake mushrooms and cook for 3 to 4 minutes until softened.
Pour in the chicken broth, then stir in the soy sauce, rice vinegar, and sesame oil. Bring to a gentle simmer and cook for 5 minutes.
Add the carrots and napa cabbage. Simmer for about 3 minutes until just tender.
Carefully add the frozen potstickers to the pot. Cook according to package directions, usually 5 to 7 minutes.
Add the bok choy during the last 2 minutes of cooking, just until wilted and bright green.
Ladle the soup into bowls and top with green onions. Enjoy warm!