Step 1

In a large pot, bring the stock, vinegar, soy sauce, sesame oil, and ginger to a boil.

Step 2

Reduce to a simmer and add the mushrooms. Let them gently boil for five minutes.

Step 3

Add the noodles and boil for another four minutes (or time according to package directions).

Step 4

Remove the pot from heat and add the bok choy. Cover and allow bok choy to wilt for one to two minutes.

Step 5

Ladle into bowls and serve immediately. Serve with chili garlic sauce or sliced chilis if desired.