Hearty Grilled Tenderloins
In medium saucepan, over medium-high heat, cook onions in margarine until tender. Add tomatoes, ¼ cup steak sauce and vinegar; heat to a boil. Reduce heat and simmer 5 minutes. Remove from heat; stir in parsley. Keep warm.
Grill steaks over medium heat 5 minutes on each side or until desired doneness, brushing with remaining steak sauce. Serve steaks with warm sauce.