Rinse pork; dry and trim excess fat. Cut tenderloins in half crosswise then slice almost through and butterfly, pounding lightly to flatten. In a food storage bag, combine soy sauce, sherry, and lemon juice. Add grated or powdered ginger. Turn pork in marinade to coat. Refrigerate for 1 to 2 hours.
Preheat broiler and cover broiler pan with aluminum foil.
Broil pork, browning on all sides, basting w/marinade once or twice.
Cook for about 5 to 6 minutes on each side, until pork is done (about 160°).