Steak Diane
["1 Tbsp. reduced-calorie margarine, melted", "2 Tbsp. low-sodium Worcestershire sauce", "3/4 lb. fresh mushrooms, sliced", "1 c. chopped onion", "4 (4 oz.) beef tenderloin steaks (1-inch thick)", "1/4 c. Dijon mustard, divided", "1/4 c. brandy"]
["Combine margarine and Worcestershire sauce in a large nonstick skillet; place over medium heat until hot.", "Add mushrooms and onion; saute until tender.", "Place steaks between 2 sheets of heavy-duty plastic wrap; flatten to 1/4-inch thickness, using a meat mallet or rolling pin.", "Spread 1 1/2 teaspoons mustard on one side of each steak.", "Move mushroom mixture to one side of skillet. Add steaks, mustard side down.", "Cook steaks 3 to 4 minutes over medium heat.", "Stir mushroom mixture occasionally.", "Spread 1 1/2 teaspoons mustard on top side of each steak; turn and cook 3 to 4 minutes on second side of steak or to desired degree of doneness."]
["margarine", "Worcestershire sauce", "fresh mushrooms", "onion", "beef tenderloin", "Dijon mustard", "brandy"]