For rack of lamb that’s evenly medium-rare from edge to edge, sous vide cooking is by far the best approach. It works because slow, precise cooking followed by high heat gives you perfectly even results with a nice dark crust. Basting with butter and aromatics during searing adds flavor to the lamb.
Lamb tends to be leaner and smaller than a steak, which means that it’s even more susceptible to accidental overcooking. All of this makes it an ideal candidate for cooking sous vide, which makes overcooking nearly impossible and perfectly edge-to-edge medium-rare results the norm.
With sous vide, the doneness of a lamb rack is by and large determined by the maximum internal temperature it reaches during cooking. For instance, so long as the interior does not rise above 130°F (54°C), it will never cook beyond medium-rare—which works for us!
The down side? It takes longer. A traditionally cooked rack of lamb goes from fridge to plate in about 30 minutes. A sous vide rack of lamb will take more than an hour, though, with sous vide cooking, this time is almost 100% hands-off. We add thyme or rosemary sprigs, along with sliced shallots and garlic cloves (but no added fats such as butter or oil) to the bags with the lamb during cooking. Adding the same aromatics to the pan as you sear will bolster that flavor further.
Because sous vide techniques cook from edge to edge with more or less perfect evenness, there is no temperature gradient inside. A medium-rare rack of lamb should be 130°F from the very center to the outer edge, with only the outer surfaces hotter after searing. Thus, sous vide lamb can be served immediately after searing.
So have all of your sides ready. Our lamb was paired with the most fabulous Cheesy and Creamy Fennel Gratin and perfectly roasted asparagus.
recipe title=”Sous Vide Rack of Lamb” servings=”4″ time=”2 hr, 15 min” difficulty=”easy”]
- 2 (8-bone) racks of lamb, about 2 lbs. total
- Kosher salt and freshly ground black pepper
- Aromatics, such as fresh thyme or rosemary sprigs, sliced shallots, and sliced garlic
- 2 Tbsp. vegetable, canola, or rice bran oil
- 2 Tbsp. unsalted butter
- Preheat a sous vide immersion circulator to desired final temperature according to chart above and in notes section. Season lamb generously with salt and pepper. Place racks in two individual sous vide bags, along with herbs, garlic, and shallots, and distribute evenly. Seal bags using a vacuum sealer, or seal plastic zipper-lock bags using the water displacement method. Place bags in preheated water bath (130°F/54°C for medium-rare) for 2 hours.
- Remove lamb from bags and carefully pat dry with paper towels.
- Add vegetable, canola, or rice bran oil to a heavy cast iron or stainless steel skillet set over the hottest burner you have. Preheat skillet until it starts to smoke. Gently place lamb, meaty side down, in skillet, using your fingers or a set of tongs. (Work in batches if pan is not large enough to accommodate both racks.) Add 1 tablespoon butter per rack, along with fresh aromatics. Sear first side, moving rack around pan and basting it with hot melted butter and herbs, until well browned, 30 to 45 seconds. Flip and brown second side, about 30 seconds longer. Transfer to a wire rack set in a rimmed baking sheet to rest, then repeat with second rack if necessary, using fresh butter and aromatics.
- Lamb can be immediately carved and served as directed in step 5. Alternatively, allow it to rest for up to 10 minutes while you set the table. To re-crisp, reheat pan drippings until smoking-hot, then pour them over resting lamb racks just before carving and serving.
- Transfer cooked lamb to a cutting board. Carve it by holding rack upright (the bones make a good handle) and slicing down after every two rib bones with a sharp knife. You’ll have to work your knife around a little bit to find the joint between the vertebrae as you reach the bottom. (Don’t force your knife through a bone, or you may chip or dull it.) Serve immediately.
Recipe by J. Kenji López-Alt for Serious Eats