Combine 1 tablespoon of crushed peppercorns, mint, garlic, vinegar, soy sauce and red wine in a shallow bowl. Marinate the lamb for approximately 8 hours, occasionally turning. Remove roast from marinade. Reserve marinade; roll and tie the roast. Preheat the oven to 350ºF. Spread mustard over meat and pat 2 tablespoons of crushed peppercorn onto the mustard. Set roast in shallow roasting pan. Pour reserved marinade around, not over, roast. Bake 1 1/2 hours or 18 minutes per pound. Roast will be medium rare. Let roast stand 20 minutes before carving. Serves 6 to 8 people.