Cut larding pork-strips 1/3"×2". Roll in mixed salt, pepper and ginger, and insert in larsing needle. Pull strips through meat (evenly spaced intervals), leaving both ends of fat showing at surface.
Rub meat with any remaining seasonings, then olive oil. In roasting pan, pour butter over it. Roast in 350°F oven 2½ to 3 hours (until meat is brown and tender), basting often with meat stock/bouillon.
Remove roast to warmed serving platter and keep warm. Skim fat from gravy. Rub butter and flour together and make smooth paste with a little meat stock; add this to pan drippings, adding dry wine and boil a few minutes. Add the currant jelly, grated orange peel, and Madeira/port. Cool until thickened.
Serve hot, garnished with currant jelly.