Stop! Bite! Look! Three words for judging spring rolls. Stop! Don't dunk them in that over-sweet chili concoction. Cheap rolls are packed with vermicelli noodles — little mop heads soaking up sauce. Bite! The rice paper should be al dente; firm, but you shouldn't have to gnash your teeth to get through. You should feel the pop of springtime in your mouth from fresh basil and mint. Look! What's the ratio of the stuff inside? Lots of noodles and little flecks of everything else? Not so good. What is good are the rolls at Banh Mi So #1. You can smell the basil wafting through air when you walk in. The pork-and-shrimp combo roll seems crammed with everything but noodles. In addition to the five or six other varieties on the menu, check out the specials on the whiteboard. Fried mung bean cake is a lesson in crunchy-chewy texture contrasts. If you don't order it, ask for the sauce that comes with it. It has a salty, sweet, sour, umami taste-swirl that beats the pants off other sauces. Just as Banh Mi So beats other St. Louis spring rolls.