Barbecued butterflied lamb leg

In a small bowl, combine the mustard, oil, garlic and thyme. Unfurl the lamb, cut away any excess sinew or fat and put the lamb in a large bowl. Sprinkle over the salt and pepper, then massage gently to coat evenly. Spoon the mustard mixture over the lamb and massage to coat the meat in the marinade. Leave to marinate for at least 1 hour, or ideally overnight in the fridge (bring back to room temperature before cooking, if chilled).

Preheat the barbecue with the coals banked on one side until smoking hot. (If cooking indoors, preheat the oven to 180˚C, gas mark 4 and heat a griddle pan.) Put the lamb on the barbecue directly over the hot coals (or on the griddle) and leave for a few minutes to get some colour. Flip the lamb over to colour the other side. Once browned, move it to the side of the barbecue with no coals (or put on a baking tray in the oven for 15-20 minutes). Cook for 18-20 minutes for medium (or to taste), turning and brushing often with the marinade.

Once the lamb is cooked, take it off the heat and allow to rest for 10 minutes, loosely covered with foil. When ready to serve, carve and put on a serving platter, squeezing the lemon juice all over. Sprinkle with extra thyme and serve.