Step 1

Preheat oven to 190°C. Heat 1 tablespoon of oil in a frying pan over medium heat. Add the onion and cook for 3 minutes or until soft. Add the cumin. Cook, stirring, for 1 minute or until aromatic.

Step 2

Place the couscous in a large heatproof bowl. Add the water. Cover and set aside for 3-4 minutes or until the liquid is absorbed. Use a fork to separate the grains. Add the onion mixture, date, quince paste, pistachio and parsley. Season with salt and pepper. Toss to combine. Set aside to cool completely.

Step 3

Open the lamb to lie flat on a clean work surface. Use a sharp knife to cut a deep slit in the meat where most of the bone has been removed (don't cut all the way through). Spread the couscous mixture along the centre of the leg. Roll up to enclose filling. Use unwaxed white kitchen string to tie at 2cm intervals.

Step 4

Place the lamb in a large roasting pan. Drizzle over remaining oil. Season with salt. Roast for 1 hour 10 minutes for medium or until cooked to your liking. Transfer to a large plate and cover with foil. Set aside for 20 minutes to rest before carving to serve.