The Buckhorn Exchange is in its 109th year, and unlike the hundreds of animals whose heads (and other parts) grace the walls, it's still alive and kickin'. And this restaurant really jumps at lunchtime, when the hungry hordes pile into its Old West-style dining room and dive into the pot-roast sandwich, the Buckhorn's best-selling comfort food. Good luck getting this monster into your mouth: The thick-cut black pumpernickel bread can barely hold in the fat chunks of falling-apart-tender beef brisket, which are soaked through with a dark, salty, beef pan gravy. That gravy eventually soaks through the bread, too, at which point you might as well surrender and eat the whole mess with a fork, alternating dips into the side of chunky mashed potatoes, also smothered in that good gravy.