Pre heat a fan forced oven to 180C (360F) degrees.
In a baking pan large enough to fit the lamb, cut the lemons in half and place cut side down.
Place the lamb on top so the lemons act as a trivet for the leg of lamb.
With a small knife, make three deep incisions in the lamb about 6 cm apart.
Insert the garlic cloves into each incision.
Sprinkle the lamb with the ras el hanout and rub into the lamb thoroughly.
Place lamb into oven and cook for 1 hour 20 minutes.
Remove lamb from oven, cover with aluminium foil and allow to rest for 10 minutes.
Place all ingredients in a bowl and combine.