This is the recipe for a meat course that was the fifth course of a meal actually served on the Titanic. This recipe is in a book my son has about the ship. I believe the instructions have been altered for today's appliances.
Trim lamb of gristle and excess fat. Stir together garlic, 2 tbsp of the oil, rosemary, mustard and pepper; rub over surface of meat; marinate at room temperature for 1 hour or in refrigerator for up to 48 hours. In large heavy skillet, heat remaining oil over high heat; add leg and sear, turning often, for about 5 minutes or until well browned on every side.
Place leg in roasting pan. Pour wine and salt into skillet and bring to a boil, stirring to scrape up any brown bits; pour over meat. Cook lamb in 450F oven for 15 minutes; reduce heat to 350F and continue to roast for 25 minutes for a rare roast or for 35 minutes for medium rare. Remove roast from pan and let rest for 15 minutes.
MINT SAUCE: Meanwhile, place roasting pan over medium heat. Stir in shallots and cook, stirring often, for 5 minutes or until softened. Stir in wine; bring to boil and cook, stirring, for 1 minute or until reduced to a glaze. Stir in stock, vinegar, and sugar. Continue to boil rapidly for 2 minutes or until sauce is slightly thickened; pour through a fine-meshed sieve. Stir in mint. Serve sauce alongside roast. Garnish with fresh mint sprigs.