Lamb is an often overlooked choice, but it’s one of our family’s favorites! If you want to give a Roast Leg of Lamb a try (perfect for a special occasion) this recipe is absolutely fool-proof!
Roast Leg of Lamb Recipe
My dad can be a bit of a homebody, but there is one surefire way to get him over to our house.
Tell him we’re cooking lamb.
Lamb is such a special treat, but so many people have not had the pleasure of enjoying perfectly cooked, succulent lamb… without that nasty mint sauce!
If you’ve only ever known lamb served with that florescent green jelly, this recipe is going to be a revelation for you in how lamb is supposed to taste. It only takes 5 minutes to prepare this recipe, yet the flavor will make it seem like you’ve been in the kitchen all day!
However, if you’re not ready to splurge of a whole leg of lamb, this recipe can be made using lamb chops (just be sure to sear them before baking) or you can try out one of our other lamb recipes to test the waters, like our Lamb Shepard’s Pie or our Lamb Burgers with Caramelized Onions and Feta.
Leg of Lamb Cooking Time
Unlike beef, lamb should never, ever be cooked until brown throughout – that is a surefire way to tell that it is overcooked.
Lamb should be still pink when you cut into it and an inserted meat thermometer should read at least 145ºF.
The exact cooking time is going to depend on a couple of things – whether you let the lamb come to room temperature before cooking, how big your leg of lamb is, whether the lamb was ever frozen, etc. However, a 4-5lb bone-in leg of lamb will take approximately 1 1/2 to 2 hours to cook.
Give yourself extra time – you can always keep the leg of lamb warm on the lowest setting of your oven if it is fully cooked before you are ready to serve. (And if it does end up taking a bit longer than you anticipated, chop up some veggies or fruit and set them out with dip to keep the kids happy as the lamb finishes up.)
|Lamb Leg, bone in||5 to 7 lbs.||Roast 325°||20 to 25 min./lb.||Medium rare 145°|
|25 to 30 min./lb.||Medium 160°|
|30 to 35 min./lb.||Well done 170°|
|7 to 9 lbs.||Roast 325°||15 to 20 min./lb.||Medium rare 145°|
|20 to 25 min./lb||Medium 160°|
|25 to 30 min./lb.||Well done 170°|
By the way, the difference between bone-in leg of lamb and boneless comes down to a couple things: bone-in is going to be a lot cheaper and it’s going to have more moisture. However, it may take a bit longer to cook. you can also save those bones and make a delicious homemade stock afterwards.
How to Score Leg of Lamb
Like with our our roasted duck recipe, I scored the meat on this Garlic and Herb Roast Leg of Lamb for a couple of reasons:
- Leg of lamb can be a bit fatty, so scoring the fat/skin of the lamb will allow some of that fat to cook out while steal ensuring a juicy, succulent meal
- Scoring the meat also allows the marinade flavors to be absorbed into the meat, especially if scored and marinaded overnight
You do not need to make a deep cut to score meat, just 1/4″ into the meat will do.
Use a sharp knife to cut across the meat one way, and then making perpendicular (criss-cross) cuts the other way. Then season as desired.
Those scores also are great for nestling herbs and slices of garlic for even more flavor.
What to Serve with Lamb
I roasted our leg of lamb with mini potatoes and jewel-colored beets, but you can serve lamb with plenty of different side dishes, such as:
- Creamy Potato Pea Salad
- Garlic Parmesan Risotto
- Irish Colcannon Mashed Potatoes
- Roasted Potatoes with Garlic and Rosemary
- Roasted Carrots with Fresh Rosemary
- Honey Roasted Carrots
- Skillet Roasted Asparagus with Lemon, Garlic and Rosemary
Garlic Roasted Leg of Lamb Ingredients
- 1 leg of lamb, approximately 4-5lb
- 1/4 cup olive oil, plus more for the vegetables
- 2 Tablespoons butter
- 6 garlic cloves, crushed
- 2 teaspoons Italian seasoning
- 4 cups mini potatoes, halved
- 4-5 small beets, quartered
- Salt and pepper, as needed
Tip: swap out the Italian seasoning for Greek, if you prefer.
Kitchen Tools You May Find Helpful
- Sharp kitchen knife
- Measuring cups and spoons
- Sheet pan
- Pastry brush
- Microwave-safe bowl
- Meat thermometer
How to Roast a Leg of Lamb
Preheat oven to 400ºF
In a small pan or microwave-safe bowl, combine the crushed garlic, olive oil, butter and Italian seasoning. Heat until the butter is melted.
Place the lamb on a clean cookie sheet.
Score the leg of lamb using a sharp knife. Cut across the meat one way, and then making perpendicular (criss-cross) cuts the other way, as shown.
Brush the oil-butter mixture all over the lamb, ensuring to get lots of the marinade into the cuts. You can also wedge the crushed garlic into these cuts to infuse the meat with incredible flavor.
Place the leg of lamb in your preheated oven. The total cook time will be 1 1/2 hours to 2 hours, until an inserted thermometer reads at least 145ºF for medium rare, however, if you are also roasted potatoes and beets as I did, you will remove the lamb at the 45 minute mark to add the vegetables.
Chop the vegetables as desired, and then toss with additional oil and Italian seasoning.
Spread out evenly on the cookie sheet and return to the oven.
When the roast leg of lamb is done cooking, cover with tinfoil and let rest for 5-10 minutes before cutting into it to serve.
Grab your free printable for our best leg of lamb recipe:
This roast leg of lamb is a perfect main course for Easter, Christmas, or just a special Sunday supper – and it’s shockingly easy to make! Everyone will think you put in hours of effort, but it only takes 5 minutes.