WHEN THE CHIPS ARE DOWN At the heart of most debates about which barbecue tastes best is the kind of wood used to smoke it. Most Texans favor mesquite or hickory, which home cooks can buy in chip form. Mesquite provides a mild, clean smokiness; hickory smoke is heavier and sweeter. The smoke flavor of choice is so essential to the formula of a barbecue that restaurants keep their wood supplies under lock and key. Commercially smoked meats cook in specially constructed ovens, some of which are big enough to walk into. At one end of the oven, wood is burned down to coals. The meat goes into the oven, well away from direct heat of coals and cooks for hours at carefully maintained (with regular addition of coals) low temperatures. When the meat emerges, it has the deep, rich color of mahogany. THE BEEF COMES FIRST In this state, where cattle reign, beef brisket sets the standard for good barbecue. When cooked long and slow, this fibrous, chewy cut becomes tender and moist. And when sliced across the grain, its downright delicious. Serve it plain or tucked into soft buns with Sam Higginss lively barbecue sauce. While the beef cooks, other meats such as chicken, spareribs, sausages, and ham usually share grill and smoke, achieving equal succulence. Higgins has reduced his massive recipe so it will work on a standard covered (kettle) barbecue using charcoal briquets and wood chips. In this unit, you can smoke a beef brisket, a rack of pork spareribs, and a chicken-enough to serve 20 to 24 people. The technique is easy. First, rub meats with a blend of salt, pepper, paprika, and chilies, then sear them briefly over hot coals to brown. Push the coals to one side of the fire grate; sprinkle them with a few soaked wood chips for slow, steady smoke, and place meats on the grill-but not over coals. Cover the barbecue and regulate vents to maintain a low temperature for at least 3 hours. THE TEXAS TWO-STEP After the brisket smoke cooks, it needs 3 hours of slow oven-baking. This turns making Texas barbecue at home into a two-step process. Higginss recipe takes one rather long day; alternatives that follow split the cooking time between two days.