1Heat gas or charcoal grill. In medium bowl, mix all ingredients except buns, ketchup and pickles. Shape mixture into 6 patties, about 3/4 inch thick.
2Place patties on grill rack over medium heat. Cover grill; cook 10 to 15 minutes, turning once, until meat thermometer inserted in center of patties reads 160ºF. Add buns, cut sides down, for last 4 minutes of grilling or until toasted.
3Top burgers with ketchup and pickle planks; serve on buns.