Bring vegetable stock to a boil over medium heat
Add mushrooms, tofu, baby corn, bamboo shoots, water chestnuts, ginger, soy sauce, and salt to the pot of stock. When pot returns to a boil, reduce to medium-low heat and add the cabbage.
In a cup or glass, combine the cornstarch with 1/4 cup water. Stir well to form a slurry. The cornstarch should be dissolved. Use a fork or whisk for best results.
Combine the white pepper and vinegar in a small bowl. Stir well.
When the cabbage is cooked, about 5 minutes after adding it, stir the cornstarch slurry into the pot of soup.
Remove the pot from the heat. Add the white pepper vinegar mixture and stir well.
Taste the soup. Add salt or vinegar as needed.
Serve hot and garnish generously with cilantro and sesame oil.