1 pound lean ground beef
1 large egg white
2 tablespoons ketchup
1 tablespoon + 1 teaspoon drained prepared white horseradish
2 teaspoons Dijon mustard
Scant 1/2 teaspoon salt
Freshly ground pepper to taste
Barbecue sauce (store- bought), for serving
Use a fork to combine all of the ingredients except the barbecue sauce in a mixing bowl. Gently shape the mixture into 4 equal burgers. Cover with plastic wrap and refrigerate for at least 2 hours or up to 6 hours to allow the burgers to firm up. Prepare a medium-hot barbecue fire with a few chunks of water-soaked mesquite wood. Or, alternatively, put the broiler rack 6 inches from the heat source and preheat the broiler. Grill the burgers over a medium-hot fire (or broil them) until they are very browned on one side. Use a spatula to carefully turn them. Grill (or broil) to the desired doneness. Serve hot, with barbecue sauce on the side.
Makes 4 to 6 servings.