To make the broth, heat the olive oil in a small soup pot over medium heat. Once the oil is hot, add the onions, ginger and garlic, and sauté for 5 to 6 minutes, until the onions begin to caramelize slightly.
Pour in 1 cup of the vegan chicken broth and scrape up any brown bits at the bottom of the pot with a wooden spoon. Add the remaining 7 cups of broth, dried mushrooms (if using), soy sauce, rice vinegar, and sesame oil. Once the soup reaches a light boil, cover and simmer, partially covered, for 30 minutes to 1 hour. After the broth has simmered for the desired time strain it through a fine-mesh sieve and discard the vegetables and mushrooms. Return the strained broth to the pot over medium-high heat.
Meanwhile, combine all the wonton filling ingredients, mixing well to combine. Set aside for a few minutes (about 5-10) while the broth is simmering.
Carefully drop teaspoon-sized balls of the filling into the simmering broth and cook, covered for 15 minutes, until heated through.
Stir in the bok choy and simmer until just tender, 2 to 3 minutes.
Last, drop the wonton wrappers into the soup one at a time, while stirring to prevent them from sticking. Once all the wontons have been added, simmer another 2 to 3 minutes.
To serve, gently ladle the broth and some wontons into a large soup bowl. Garnish with the green onions and chili oil and enjoy immediately.