In a large pot, heat the sesame oil over medium heat. Add the minced garlic and grated ginger, sautéing until fragrant, about 1 minute.
Add the sliced shiitake mushrooms and cook for another 2-3 minutes until they soften.
Pour in the chicken or vegetable broth and bring to a simmer.
Stir in the soy sauce and add the julienned carrot and bok choy. Let it cook for approximately 5 minutes until the vegetables are tender.
Carefully add the gyoza to the pot and cook according to the package instructions or for about 5-7 minutes if they are fresh, until they're heated through.
Taste the soup and adjust seasoning with salt and pepper as needed.
Once everything is cooked, ladle the soup into bowls, garnishing with chopped green onions and fresh cilantro.
Notes
Feel free to customize the vegetables based on your preference.