This is my favorite chain restaurant soup -- the broth is the best part because it is nicely spicy and a little sour.  Can anyone make a vegetarian version of this or recommend a similar, but vegetarian, soup recipe if you've had this one/know how this one tastes?

PIN RICE NOODLE SOUP: Pork dumplings, shrimp, green onions and bean sprouts in a spicy chicken broth.  Ingredients: Pork meatballs, shrimp, pin rice noodles, bean sprouts, chili paste, chicken broth, cilantro, green onions, oyster sauce, white vinegar

Link to their menu/site:
http://www.pfchangs.com/cuisine/menu_main.jsp#soupsandsalads

-Celeste