Heat grill. When ready to grill, place steaks on gas grill over medium heat or charcoal grill 4-6" from medium coals. Cook 14-25 minutes depending on desired doneness, turning once. In small saucepan, combine cheese spread, half & half and pepper; blend well. Cook over medium heat until cheese melts and mix is smooth, stirring constantly. Stir in mushrooms until heated, stirring constantly. Serve over steaks.