In a small bowl, combine the first seven ingredients. Crumble beef over mixture and mix well. Shape into four patties.
Grill, covered, over medium heat or broil 4 in. from the heat for 5-7 minutes on each side or until a thermometer reads 160° and juices run clear. Top with cheese. Cook 1-2 minutes longer or until cheese is melted. Serve on buns with lettuce and tomato if desired.