Cook bacon in a 12-inch heavy skillet over medium heat, stirring occasionally, until crisp, then transfer with a slotted spatula to paper towels to drain. Cool to room temperature, about 5 minutes. Holding one fourth of beef in your palm, make a depression in beef and add one fourth of bacon to depression. Pull beef over bacon to enclose completely, then flatten into a 3/4-inch-thick patty (4 inches in diameter). Make 3 more patties in same manner with remaining beef and bacon. Prepare grill for direct-heat cooking over medium-hot charcoal (medium heat for gas). Season patties on both sides with salt and pepper. Oil grill rack, then grill patties, covered only if using a gas grill, turning over once, 5 to 8 minutes total for medium-rare. (Burgers will continue to cook slightly after being removed from grill.) Assemble burgers with buns and accompaniments.