1Heat closed medium-size contact grill for 5 minutes. In medium bowl, mix beef, onion, parsley, 3 tablespoons of the dressing and the pepper. Shape mixture into 4 patties, about 3/4 inch thick.
2Place patties on grill. Close grill. Grill 4 to 6 minutes or until meat thermometer inserted in center of patties reads 160ºF and patties are no longer pink in center. Top each patty with cheese slice. Let stand on grill about 3 minutes or until cheese is melted.
3Spread remaining ranch dressing on cut sides of buns. Place cheese-topped patties and pickles in buns.