Toss the vegetables and bay leaves together in bottom of a shallow roasting pan; pour water over the vegetables and place lamb, rounded side down, on vegetable mixture.
Roast at 500Â°F 25 minutes.
Remove meat from oven and reduce oven temperature to 300Â°F.
Turn meat, rounded side up; sprinkle with a mixture of the salt and pepper.
Insert meat thermometer so tip is slightly beyond center of thickest part of meat, being careful that it does not rest on bone or in fat.
Return to oven and continue roasting until thermometer registers 180Â°F, about 3 hours.
Transfer roast to a heated platter and keep it warm.
Strain liquid from roasting pan and skim off excess fat; reserve about 1 cup liquid for sauce.
Garnish platter with spiced crab apples and parsley.
Accompany with the sauce.