"All men should try to learn before they die what they are running from, and to, and why." James Thurber, who emitted that bon mot, preferred the Algonquin to Nachomama's. Of course, Thurber didn't live in St. Louis, and he shuffled off this mortal coil more than 30 years before John and Nancy St. Eve conceived the Tex-Mex joint that has since become a local institution, so we can only speculate about what the Thurbster might have said about one of the 'Mama's fajita platters. (Probably safe to say, though, that he would have ordered a margarita while he was squinting up at the menu.) The joint has a drive-thru window, so there's no quibbling about whether it qualifies for this category. Despite that designation, Nachomama's is a blessing to those in whom the mere notion of "fast food" inspires indigestion. We go for the $7.25 wood-roasted chicken platter -- half a bird, marinated and grilled till the skin singes to a salty-spicy near-nonexistence that melts in your mouth, served with grilled onions, fresh shredded cabbage, tortillas, beans and rice -- accompanied by a flowerpot full o' chips ($1.89; also available in smaller incarnations), a scoop of house-made salsa and an ice-cold beer from the tub by the door. You, on the other hand, may veer toward a portobello quesadilla and a lemonade. No matter. We're both here because we want terrific food and no dawdling. So what are you waiting for? Order already, and dig in.