Prepare your ingredients.
In a medium stockpot, add the chicken, mushrooms, carrot, bamboo shoots, whites from the green onions and the chicken stock. Place the stockpot over high heat and bring to a gentle simmer.
Once you have a simmer in the pot, add the soy sauces, vinegars, white pepper and tofu. Reduce heat to medium and simmer for 2-3 minutes or until mushrooms are just softened.
Now create the cornstarch slurry with 3TBSP of cornstarch and cold water. Add the cornstarch slurry to the soup and stir. Simmer for another 3 minutes to thicken.
Stirring the soup, add the whisked egg to form egg ribbons.
Taste the soup and adjust the seasoning to your taste, i.e. add salt (to enhance the flavors, vinegar (for more sour) and/or pepper (for extra heat).
Ladle the soup into bowls and top with the green onion tops. Enjoy and cheers 🥂.