What many don’t realize is that prepping and cooking a big cut of meat can actually be easier and more forgiving than working with smaller cuts. According to chef Alan Bergo, you just need to know a few basic principles, and have a simple trick or two up your sleeve. Here he shares his favorite method for serving up a flawless roast leg of lamb on your first try. It employs a surprisingly simple kitchen hack known as the reverse-sear.
Truth be told, while we’ve done the reverse-sear method on a number of cuts of beef, this was our maiden voyage with lamb. In this case, the recipe called for a 3-4 pound leg of lamb, but ours was nearly 5 pounds so the cooking time was actually 2 hours and 20 minutes. We used an internal thermometer to measure the temperature the entire time it was roasting.
One ingredient not included in the original recipe was garlic, so we included 4 cloves and mashed them in a large mortar with salt. Next we added the herbs (which we increased from 1/4 cup to a 1/2 cup since our roast was larger), and mashed it altogether to make a paste.
The lamb entrée was paired with Smashed Sage-Butter Potatoes that were so tender and creamy and Balsamic Roasted Brussels Sprouts and Shallots. A word to the wise on the potatoes: make sure to get the small baby Yukons. This time around the store wasn’t carrying them, and we picked up 3+” potatoes, shown below. They came out wonderfully creamy, but the sagey butter didn’t really penetrate into the interiors as much.
Perfect Reverse-Seared Leg of Lamb
- 1 Boneless leg of lamb (3-4 pounds)
- Flavorless high heat cooking oil, like grape seed
- 1/2 cup aromatic herbs like rosemary sage and thyme, finely chopped
- 4 cloves of garlic, peeled and mashed in a mortar with salt
- 2 tsp. kosher salt or more to taste
- 1 tsp. fresh ground black pepper or more to taste
- Extra-virgin olive oil
- In a large mortar, mash the garlic cloves with kosher salt until pulverized. If using rosemary, mash that with the garlic and then finish with the remaining herbs.
- Season the meat with salt, pepper and the garlic-herbs paste inside and out. Roll the leg up tightly and tie with kitchen twine to ensure even cooking. Let it sit uncovered in the fridge overnight.
- The next day, 1 1/2 hours before you want to serve (assuming a 3-4 lb leg) preheat the oven to 250 °F and place the leg in the oven. Insert an internal thermometer if you have one and set it for 130° for medium-rare. If all you have is an instant-read thermometer, start checking after one hour to monitor the meat doneness.
- When the internal temperature comes up to your target temperature (which could be 2 hours or more), remove the leg from the oven and allow to cool on its rack loosely tented with foil in a warmish location for 15-20 minutes.
- Finally, rub some extra-virgin olive oil all around the roast and heat a few tablespoons of grape seed oil in the sauté or cast iron pan on high. Turn on the hood, and or open a window, since you’ll be using some high heat for a few minutes. When the oil is just starting to smoke gently, reduce the heat to medium-high and brown the roast deeply on all sides.
- After the roast is browned, transfer to a cutting board, remove the twine, cut into slices with a sharp knife and serve immediately.
Original recipe by Alan Bergo