Heston’s tips
To cook in the oven and finish on a barbecue:
1. Prepare and season the lamb as in steps 1 and 2 in the recipe. Cover and leave at room temperature for 20 minutes to allow the salt to penetrate the meat, and for the temperature of the meat to come up a little. Preheat the oven to 110ºC, gas mark 1/4.
2. Place the lamb fat-side down on a foil-lined roasting tin. Bake for 1 hour - 1 hr 15 minutes, until cooked but still pale. If using a probe, you are looking for 50-55ºC in the thickest part. Wrap the lamb in the foil and leave to rest for 15 minutes. Meanwhile, set up your barbecue so it's hot and ready to cook. Add the olive stones to the coals, if using charcoal (see below).
3. Put the lamb fat-side down on the barbecue, using tongs, and cook as step 3 in the recipe. If you have a probe, take a measurement in the thickest part of the meat; you are looking for between 60-65ºC at this point.
4. Smoke the lamb over the herbs as in step 5 of the recipe above, then let it rest for 10-15 minutes. After resting, the temperature of the lamb will slowly rise to between 65-70ºC. Slice thinly, season with a few flakes of sea salt and enjoy.
Olive stones:
Olive stones burn at a very high temperature and emit a lot of heat. If you have some, add them to the coals after lighting.
Measuring with a probe:
Barbecuing this lamb is about connecting with one beautiful ingredient; the feel, smell and flavour - and keeping the cooking simple. However, using a probe to measure cooking temperatures can still be helpful, so they are included in this recipe.
Cooking on a barbecue isn’t a precise art, and each piece of lamb will vary too. Barbecuing the lamb from raw, as above, will give meat that’s medium. Cooking it in the oven then finishing it on the barbecue will give medium-well done. Both methods are ideal for lamb leg, a cut that needs that little bit more cooking but will stay succulent.
Always make sure the surface of the meat is thoroughly cooked.