Hot and sour soup

It feels like I've broken a record for soup eating this winter. When it's cold and frozen outside, eating soup just seems right. Now that the end of winter/beginning of spring is theoretically approaching, many people seem to get change-of-season colds, and here's a soup that seems just right for pampering a cold. The recipe creates a mild-mannered broth, but you can make it as spicy as you desire. But, don't wait to be sick to try it. We had it for dinner and we're perfectly healthy!

Hot and sour soup (based on a recipe from about.com)
6 cups low sodium vegetable broth
2 cups fresh mushrooms, sliced (some should be shiitake)
1 small can water chestnuts, sliced
2 tablespoons soy sauce
1/2 teaspoon pepper
2 tablespoons rice vinegar
1 teaspoon hot sauce
3 cloves garlic, minced
1 carrot, sliced
8 ounces water-packed firm tofu, cut into cubes
1/2 cup scallions, sliced
3-4 cups chopped bok choy
1 teaspoon toasted sesame oil
rice thread noodles

Bring broth to simmer and add all ingredients except scallions and bok choy. Simmer 20 minutes. Add bok choy and scallions and simmer 5 more minutes. Add toasted sesame oil. (Add additional soy sauce, hot sauce or vinegar, if desired.)

Put the rice noodles in a pot of boiling water for about 30 seconds, to soften. (or follow directions on the package - they vary a bit in cooking times) Place some noodles in each bowl and ladle soup over.