In a large bowl, combine beef, horseradish mustard and 1/4 tsp. each salt and black pepper; mix well. Shape into four 3/4-inch thick patties.Advertisement
Grill patties on rack of a covered gas or charcoal grill directly over medium heat for 14 to 18 minutes or until done (160° F), turning once. Top burgers with cheese during the last minute of grilling. Serve on toasted buns with warm barbecue sauce. Add arugula, tomato and/or onions.