Cut small incisions in the pork at 1-inch intervals so the marinade can penetrate the meat. In a medium bowl, combine the soy sauce, honey, sherry, hoisin sauce, five-spice powder, salt, and pepper. Add the pork; rub to coat well. Cover with plastic wrap and refrigerate a minimum of 6 hours or overnight. Turn the pork occasionally as it marinates.

Position a rack about 6 inches from the broiler and heat the broiler. Set a rack in a small roasting pan and add 1/4 inch of water to the pan. Remove the pork from the marinade (discard the marinade) and lay it on the rack. Broil with the oven door closed, turning the tenderloin after 10 minutes, until an instant-read thermometer registers 145 degrees F, 15 to 20 minutes total; keep an eye on it to avoid burning. Let cool before using.