Sous-vide Lamb

The usual procedure is to rinse the cut, pat it dry, annoint it with olive or another oil, add light salt, pepper and herbs to taste such as rosemary, sage or thyme. I like to poke into a roast at many points with a sharp paring knife and slide in thin slivers of fresh-sliced garlic something my mother-in-law (from Alsace-Lorraine) always did.

Put it into a bag, suck and seal it. Once the time has passed, sear under broiler, in pan or over a grill at highest heat to finish. Lamb should be served rare or medium rare in thin slices. Pictured here it's medium rare.

The longer cooking time tenderizes better while the shorter one suffices for heating it through. Do not exceed time by too much or the surface will become mushy.

If (inexplicably) you want it more done, add a couple of degrees to the cooking temperature.

Cut	Weight	Temperature	Time
Leg	3lbs	128-130°	4-6 hours

In my experience, 130° for 6 hours will render a 3-pound roast medium (not medium rare let alone rare as above). So, if you want rare (as I do), dramatically reduce the temperature. The longer cook time is to ensure that the connective tissue is adequately gelatinized.

Nota bene

Be very careful using the liquid left over after your meat has cooked in its bag. You'll be tempted to make gravy from it and that is a good thing, but you should know that it will very likely be too salty by far. Adjust the salt used accordingly (next time). You can mitigate the saltiness somewhat by serving a side of potato and putting the sauce over that.