Hot & Sour Soup My Way

Clean and slice the portobello mushrooms. Place them in a suitable sized sauce/soup pan.
Add the chicken broth and begin to cook over medium heat.
Slice the onion and then cut the slices in half. Peel and mince the ginger.
Add the onion, minced ginger and coleslaw mix to the soup and continue to cook.
Add the soy sauces, rice vinegar, sesame oil, and white pepper. As soon as the soup comes to a boil, lower the heat and continue to simmer until the cabbage is tender. Taste the soup. If you want the spice level hotter, add more white pepper. If you think the salt level from the soy sauce isn't enough, add some salt.
Mix the cornstarch with either water or chicken broth and mix to form a slurry.
As you are swirling the soup with a spoon, add the cornstarch slurry and mix thoroughly and continue to simmer the soup.
Place the egg whites in a small bowl and beat with a fork. Use a fork to swirl the soup as you slowly add the egg whites to the soup. You are looking to generate ribbons or small pieces of egg whites in the soup as opposed to big clumps of egg white.
The egg white will cook rapidly as it hits the hot soup. Once all the egg white has been added continue to simmer the soup for another couple of minutes.
Remove the soup from the heat. Ladle up a bowl and serve. If you have green onions, you can cut a few slices and sprinkle it over the top of the soup as garnish.
Refrigerate leftovers.