Funny how many countries love to stuff food into other food. The Chinese have their won tons, the Italians their ravioli and manicotti, the Mexicans their tamales, the Argentineans their empanadas. In Honduras and El Salvador, the dumpling of choice is the pupusa, a masa patty filled with beef, cheese and/or vegetables. At Los Catrachos, St. Louis' only Honduran restaurant, owner Dennis Machado likes to keep regulars guessing: Some days they're stuffed with gooey cheese and fried thin and crisp; other days there may be meat inside and a doughier, softer pastry. But any local foodie should be happy to take <\#213>em any way he or she can get <\#213>em: as a true delicacy, a perfect appetizer orat only three bucks a popjust the right between-meals snack.