Burger of the Week: Smoked Meat Loaf Burgers with Grilled Onion

   SERVES: 4 PREP time: 15 minutes grilling time: 8-10 minutes special equipment: 2 large handfuls mesquite wood chips   PATTIES: 8  ounces ground chuck (80% lean) 8  ounces ground veal 8  ounces lean ground pork 2  large eggs, beaten ¾  cup dried Italian-seasoned bread crumbs ¼  cup freshly grated