1Cook first 5 ingredients in frying pan until all liquid is absorbed and mixture resembles a paste.
3Partially thaw pastry shells and roll out thin enough to cover top, sides, and part of the bottom of each steak.
4Cover with plastic wrap and store in refrigerator until serving time.
6Cook steaks on rack, uncovered, for 25 minutes.
7They will be rare but will continue cooking while dish is readied.
8Serve with Bearnaise sauce.