Ciorbă is a distinctive type of Romanian soup that is soured with vinegar, sauerkraut juice or another sour agent. Sour meatball soup is among the most traditional of the sour soups, but cabbage ciorbă is also popular, and ciorbă de burtă (tripe soup) is considered the ultimate hangover food. Traditional versions use lovage, an herb infrequently found in the stores in North America, but which can be obtained at specialty shops or online. If you can't find it, celery leaves or parsley will do.