Keto Garlic Herb Roast Leg of Lamb
A tied boneless leg of lamb rubbed with garlic, rosemary, thyme, lemon zest, olive oil and butter, roasted on a bed of onions and served with a simple reduced pan jus. 3 g net carbs per serving.
Ingredients
- 4 lb boneless leg of lamb, tied with kitchen twine
- 8 cloves garlic, minced
- 2 tbsp chopped fresh rosemary
- 1 tbsp fresh thyme leaves
- 1 tbsp finely grated lemon zest (about 1 lemon)
- 2 tbsp fresh lemon juice
- 3 tbsp extra virgin olive oil
- 2 tbsp unsalted butter, softened
- 2 1/2 tsp kosher salt
- 1 tsp black pepper
- 2 medium yellow onions, sliced into thick rounds
- 1 1/2 cups low-sodium beef broth
Instructions
- Take the lamb out of the fridge about 1 hour before roasting. Pat it dry with paper towels.
- Heat the oven to 450°F (230°C) with a rack in the lower middle.
- In a small bowl, mash the garlic, rosemary, thyme, lemon zest, lemon juice, olive oil, butter, salt and black pepper into a paste.
- Spread the onion rounds in the middle of a roasting pan. Set the lamb on top, fat side up, and rub the herb paste all over the top and sides, pushing some into the folds of the roast.
- Roast 20 minutes, until the outside starts to brown. Without opening the door, lower the oven to 325°F (165°C).
- Roast about 1 hour to 1 hour 15 minutes more, until an instant-read thermometer in the thickest part reads 140°F (60°C). Start checking after 45 minutes. If the onions start to scorch, add 1/4 cup of the broth to the pan.
- Move the lamb to a cutting board, tent loosely with foil and rest 15 to 20 minutes. The temperature rises to at least 145°F (63°C), the USDA safe minimum for lamb roasts with a 3 minute rest.
- While the lamb rests, set the roasting pan over medium-high heat. Pour in the remaining broth and scrape up the browned bits. Simmer 6 to 8 minutes, until the liquid cooks down by about half. Spoon off extra fat and season the jus with salt to taste.
- Remove the twine, slice the lamb against the grain about 1/2 inch thick, and serve with the onions and jus spooned over.
- Refrigerate leftovers within 2 hours and reheat to 165°F (74°C).
Notes
Each serving has 3 g net carbs (4 g total carbs minus 1 g fiber). Nutrition is calculated with the onions and jus included. Bone-in option: use a 5 1/2 to 6 lb bone-in leg and roast 20 to 30 minutes longer, checking the temperature next to (not touching) the bone. The herb paste can go on up to 1 day ahead; keep the lamb wrapped in the fridge. Leftovers keep 3 to 4 days in the fridge; frozen sliced lamb with a little jus is best within 2 to 3 months.