1In a large skillet over medium heat, combine the mushrooms, onion, sherry, butter or margarine and parsley and saute until all the liquid is absorbed and the mixture resembles a paste. Cover the top of each steak with the mixture.
2Partially thaw the puff pastry sheets and roll out pieces thin enough to cover the top, sides and bottom of each steak. Place the steaks on a baking sheet, cover with plastic wrap and store in the refrigerator until serving time.
3Preheat oven to 425 degrees F (220 degrees C).
4Bake steaks uncovered in the preheated oven for 25 minutes. (Note: They will be rare but will continue cooking while dish is sitting.)
Footnotes
Tip
Aluminum foil can be used to keep food moist, cook it evenly, and make clean-up easier.