you will need:
2 1/2 lb. Sirloin Steak (1 1/2 inches thick)
1/2 c. Butter or Margarine
1/4 c. chopped fresh Parsley
1/4 c. minced Onion
2 tbsp. Worcestershire Sauce
1 tsp. freshly ground Pepper
1/2 tsp. Dry Mustard
Lightly score edges of steak at 1-inch intervals. Preheat grill or broiler.
Combine butter, parsley, onion, Worcestershire sauce, pepper and mustard
in a small saucepan. Heat, stirring continually, over low heat, until
butter melts. Reserve 1/4 of the mixture.
Place steak on grill or broiler pan. Brush steaks with butter mixture.
Cook, basting frequently with butter mixture, about 6 minutes per side
for medium. Place steak on a serving platter. Cut thin slices across
the grain. Drizzle reserved butter mixture over steak.