- Start by making the marinade. Mix the garlic, baharat, turmeric, ginger, lemon, coriander and salt in a bowl to make a wet rub. Score the skin side of the lamb in opposite directions, each cut should be around 1-2 cm apart. Spread the marinade all over the meat, make sure the rub gets into the scored skin.
- Cover the lamb tightly in cling film and place in the fridge and let it marinate for 12 – 24 hours. Remembering to remove from the fridge and allow to rest for an hour before cooking.
- Preheat the oven to 180˚C/gas mark 4.
- Place the lamb on a large griddle pan, barbecue, or plancha and sear on a very high heat until dark golden all over.
- Once you have achieved a good colour on the lamb, transfer to a roasting tray and roast in the oven for another 40-60 minutes, depending on how you like it.
- While the lamb is roasting, get the sweet potatoes ready. Wash well and cut into wedges, leaving the skin on. Put in a bowl and add turmeric, mustard seeds, garlic, salt and enough olive oil to coat. Place the wedges on a baking tray and put in the oven with the lamb for the last 25-30 minutes of cooking.
- Take the lamb from the oven and allow to rest for 10-15 minutes. Turn off the heat, but leave the wedges in the oven to keep warm until serving.
- While the lamb is resting, make the black sesame sauce. Combine the black sesame paste, lemon juice and water to form a thin paste, then season to taste. If the sauce is a little too thick, add water and whisk to lessen the consistency to your liking.
- Carve and plate the leg of lamb with the sweet potatoes, chopped coriander and black sesame sauce.