Boneless Leg of Lamb 8h 130F Sous Vide : Pistachio Puree : Slow Roasted Onions and Shallots


First post of 2015!  I figured I’d start this year with a lamb recipe. Lamb season is not nearly there yet but I couldn’t wait,  exciting times ahead! Anyways, I also wanted to make a dish that featured sous vide cooking for my friends at our dinner party 2 weeks ago. This recipe is inspired by the modernist cuisine folks. Its preparation takes about 24 hours including prep and curing time but with some organization and planning it’s actually quite simple and totally worth it! Please join me on Instagram btw!!!


A roasted leg of lamb is in my opinion, the most delicious lamb cut. The meat is extremely tender, juicy with a delicate flavor that can be highlighted with herbs and garlic. A leg of lamb, bone in, might need 3-4 hours to roast until the core reaches 130F (in a conventional oven), for those of you who like rare lamb (like me!). What happens with oven roasting is that usually, the core will be rare, but the surface will be cooked to medium. Not the end of the world of course and extremely delicious regardless, but if looking for a perfect rare finish across the whole cut, sous vide is the way to go. Sous vide cooking times for this cut were all over the place when I searched online. I went with a short cooking time of 8 hours, that’s short for those familiar with sous vide cooking (I’ve experimented with longer cooking times and the meat tend to dry out), a leg of lamb should be treated like chicken breast, cooked long enough to get the core temperature where you want it, and a bit longer to pasteurize but then stop, otherwise, the meat will dry out. Ok, enough of this sous vide cooking stuff,  let’s get into it while I still have energy to type!

Ingredients (serves four):

1 boneless leg of lamb (approximately 3 kg)

Lamb Cure Mix:

2 Tbsp kosher salt
2 Tbsp chopped rosemary
2 Tbsp garlic paste

Pistachio Puree:

300g shelled pistachios
200g pistachio oil or (100g walnut oil + 100g almond oil)
100g water
1.2g Xanthan gum
salt to taste

Slow Roasted Onions and Shallots:

1 large white onion
4 large shallots or small Spanish onions
enough salt to cover the shallots
Vegetable oil


The pistachio puree. Shell all the pistachios… yes, extremely annoying and plan on going nowhere for at least one hour. Discard the shells. Place the shelled pistachios in a pressure cooker or cooking pot. Add enough water to cover them, add a little salt (if the pistachios were already salted , don’t add any). If pressure cooking, cook for 20 min. If cooking in a pot, boil for about 1 hour, covered. Strain. Add the pistachios and oil to blender. While the blender is running, add the xanthan gum. The xanthan gum will stabilize the emulsion for a long time and give the puree a silky texture while also thickening it a bit. Blend for a good amount of time.


The longer, the finer the result will be. I probably blended for a good 10 min. You will need a spatula since the puree is too viscous to blend fluidly (it’s not a smoothie). Stop the blender, stir the puree around and blend some more until everything is pureed. Adjust seasoning while blending. Once ready. Strain the puree through a fine sieve or chinoise and reserve in a jar. This puree can be made a couple of weeks in advance if kept in the refrigerator which is very convenient.


Cooking the lamb. Let’s tie up this roast first. To give it shape and ensure even cooking. In a large ziplock bag, add the cure mix. Place the lamb leg inside the bag, and distribute the cure mix evenly over the surface of the meat. Store in the fridge overnight and let the cure mix work its magic. The next day,  rinse the mix off the lamb before cooking. Also rinse the bag to reuse it. Once you’re ready to sous-vide the lamb (I don’t even know if sous-vide  is a verb) Vacuum seal (water displacement method is fine) and cook in a water bath at 130F for 5-8 hours. Another approach is to cure and cook at the same time. I like this approach when I’m running short on time and have to get things reading within the same day. Any jus released in the bag will be throw away though because the curing mix will make it extremely salty.


Remove the meat from the bag, rinse and dry with paper towels. Reserve any lamb jus contained in the bag for another use. Sear on a cast iron skillet or stainless steel one. If you chose to cook the lamb with the curing mix in the bag, brush some of the excess salt away and pat dry with paper towels before searing. I don’t bother picking out the rosemary leafs. Those sear well, they’re very resilient and actually develop a nice flavor and crispiness which adds texture contrast. Keep in a warm oven until ready to serve.

Slow roasting the shallots and the onions.  Preheat the oven at 240F (the modernist cuisine guys go for 220F, but I can’t sit by my oven for 12 hours, 240F makes it about 8 hours, a little less enslaving). Place the shallots in a deep tray, I used a metal coffee mug, the shallots aren’t that big. Mix the water and salt, the salt should have the consistency of damp sand. Make a layer of salt at the bottom of the container, place the shallots over it, and then cover the shallots with the rest of the salt. Like I mentioned, cook for 8 hours, oven door cracked. The onions go in there as well. Quarter the onion, remove the outer layer of dry skin. On a flat tray, add some vegetable oil, place the onion quarters over it. Place this tray in the oven along with the shallots. They too will cook for 8 hours. After 8 hours, remove the shallots and the onions from the oven. Reserve the salt for any use, it’s been infused with shallot flavor, don’t throw away that! Peel the outer skin layers from the onions and the shallots and reserve until ready to serve. You can place them in a warm oven along with the roasted lamb.


Plating. Using your sharpest slicing knife, fillet the roast against the grain, in the shape of medallions. Place an onion quarter per plate, along with a shallot. Add a couple of tablespoons of pistachio puree and garnish the medallion with a mint leaf. Drizzle some extra virgin olive oil and serve right away! Enjoy!