Garlic & Herb Roast Boneless Leg of Lamb

Garlic and herb roast boneless leg of lamb is a flavorful oven-roasted dinner made with tender lamb coated in fresh rosemary, thyme, garlic, Dijon mustard, and olive oil. This easy lamb roast recipe creates juicy meat with a savory herb crust and perfectly roasted potatoes cooked in the same pan. Ideal for holiday dinners, Easter meals, Sunday roasts, and special occasion recipes, this classic lamb dish combines simple ingredients with rich, comforting flavor. Perfect for anyone searching for roast leg of lamb, garlic herb lamb recipe, boneless lamb roast, or oven roasted lamb with potatoes, this recipe delivers elegant presentation with minimal preparation.

Ingredients

Lamb

• 3 pounds boneless leg of lamb (or 5–6 pounds bone-in)
• 4 garlic cloves, minced
• 1 tablespoon olive oil
• 2 tablespoons fresh rosemary, chopped
• 1 tablespoon fresh thyme leaves
• 1 tablespoon Dijon mustard
• 1 tablespoon kosher salt
• 2 teaspoons black pepper

Potatoes

• 2–3 pounds small potatoes
• 2 tablespoons olive oil

Instructions

1. Preheat the oven
   Set oven to 350°F (175°C).
2. Prepare the herb mixture
   In a small bowl, combine garlic, olive oil, rosemary, thyme, Dijon mustard, salt, and black pepper.
3. Season the lamb
   Rub the herb mixture evenly over the entire leg of lamb.
4. Prepare the potatoes
   Place potatoes in a roasting pan or casserole dish. Drizzle with olive oil and season with salt and pepper. Toss to coat evenly.
5. Arrange for roasting
   Set the seasoned lamb on top of the potatoes.
6. Roast the lamb
   Roast for 1 1/2 to 2 hours for boneless lamb, or longer for bone-in, until the internal temperature reaches 130–135°F for medium-rare.
7. Rest before serving
   Remove from the oven and let the lamb rest for 15 minutes before slicing. Serve with the roasted potatoes.

Tips

• Bring the lamb to room temperature before roasting for even cooking.
• Use a meat thermometer for accurate doneness.
• Let the meat rest before slicing to retain juices.
• Toss potatoes halfway through cooking for even browning.

Variations and Substitutions

• Add lemon zest for a brighter herb flavor.
• Substitute rosemary and thyme with oregano or parsley.
• Use sweet potatoes instead of regular potatoes.
• Add onions or carrots to the roasting pan for extra flavor.

FAQs

What temperature should lamb be cooked to?
Medium-rare is typically 130–135°F after resting.

Can I use dried herbs instead of fresh?
Yes, but reduce the amount since dried herbs are more concentrated.

How long should the lamb rest?
About 15 minutes to keep it juicy and tender.

Can I prepare the lamb ahead of time?
Yes, season it a day ahead and refrigerate until ready to roast.

Serving Suggestions

• Serve with roasted vegetables or green beans
• Pair with mint sauce or gravy
• Add a fresh salad for balance
• Serve with crusty bread for a complete meal

Why You’ll Love This Recipe

• Tender, juicy lamb with bold herb flavor
• One-pan meal with roasted potatoes
• Perfect for holidays and family dinners
• Simple preparation with elegant results

Garlic & Herb Roast Boneless Leg of Lamb

Recipe by el hassan

Servings

8 -10

servings

Prep time

15

minutes

Cooking time

1

hour 

30

minutes

Calories

277

kcal

Ingredients

• Lamb

• 3 pounds boneless leg of lamb (or 5–6 pounds bone-in)

• 4 garlic cloves, minced

• 1 tablespoon olive oil

• 2 tablespoons fresh rosemary, chopped

• 1 tablespoon fresh thyme leaves

• 1 tablespoon Dijon mustard

• 1 tablespoon kosher salt

• 2 teaspoons black pepper

• Potatoes

• 2–3 pounds small potatoes

• 2 tablespoons olive oil

Directions

• Preheat the oven
• Set oven to 350°F (175°C).
• Prepare the herb mixture
• In a small bowl, combine garlic, olive oil, rosemary, thyme, Dijon mustard, salt, and black pepper.
• Season the lamb
• Rub the herb mixture evenly over the entire leg of lamb.
• Prepare the potatoes
• Place potatoes in a roasting pan or casserole dish. Drizzle with olive oil and season with salt and pepper. Toss to coat evenly.
• Arrange for roasting
• Set the seasoned lamb on top of the potatoes.
• Roast the lamb
• Roast for 1 1/2 to 2 hours for boneless lamb, or longer for bone-in, until the internal temperature reaches 130–135°F for medium-rare.
• Rest before serving
• Remove from the oven and let the lamb rest for 15 minutes before slicing. Serve with the roasted potatoes.