Though La Buca built its rep serving basic, affordable pasta dishes (a spicy, caper-flecked plate of puttanesca rings in at $5.95), "The Mouth" is more than capable of talking like a "real" restaurant. Try a dinner special of salmon with soft polenta accented with sharp parmesan and sautéed vegetables ($10-$11)-the flavor measures up to anything you'll get at a fancy joint. (ED)