HEAT grill to medium-high heat.
MIX first 3 ingredients just until blended; shape into 8 (3-inch) patties.
GRILL 3 to 5 min. on each side or until done (165ºF). Top with cheese; grill 1 min. or until melted. Meanwhile, grill buns, cut-sides down, until toasted.
FILL buns with burgers.