Trim fat from steak. Brush both sides of steak with oil. Sprinkle with 1/4 tsp. salt and 1/4 tsp. pepper.Put steak in shallow dish. Drizzle with Worcestershire sauce. Cover and marinate in refrigerator for 2 hours.
Preheat broiler. Put steak on unheated rack of broiler pan. Broil 4 to 5 inches from heat for 18 to 21 minutes for medium rare, or 22 to 27 minutes for medium, turning once halfway through broiling. Cover loosely with foil and let stand for 10 minutes
`Meanwhile, for mushroom sauce, in large skillet, melt butter over medium heat. add mushrooms, 1/4 tsp. salt and 1/8 tsp. pepper.Cook for 8 to 10 minutes or til mushrooms begin to turn a light golden brown and liquid is evaporated, stirring occasionally. Stir in whipping cream. Bring to boiling; reduce heat. Simmer, uncovered, for 4 to 6 minutes or til slightly thickened. If desired, season with additional salt and pepper to taste. Slice steak. Spoon mushroom sauce over each serving. Serves 6 to 8