Preheat the barbecue flat-plate or char-grill plate to hot.
Lightly score the inside of the butterflied lamb leg in a criss-cross fashion. Rub the sumac over the lamb, then brush or spray lightly with oil and season with salt and pepper.
Place the lamb on the barbecue, reduce heat to moderately-hot. Cook the first side of the lamb for 20 minutes, turn with tongs and cook for a further 20 minutes. Cover lamb loosely with foil and rest if for 10 minutes before serving.
While the lamb rests add the oil to a frypan and heat over a moderately-high heat. Add the capsicum, corn, garlic and cumin. Cook for 2-3 minutes, stirring occasionally. Remove from heat and stir in the coriander and mint. Serve the sliced lamb with the corn salsa.
Recipe from Beef + Lamb NZ
