Posted on
by 
2 Comments A leg of lamb is without a doubt a classic for Christmas dinner. This easy Christmas lamb recipe with rosemary and garlic makes an impressive centerpiece without being difficult to prepare. It’s also perfect for Easter or any other festive occasion. But how do you prepare the perfect leg of lamb? I’ll walk you through it step by step.
Table of contents
Tip from Simone
Making a large piece of meat for either Christmas or Easter can be a bit daunting, but this recipe for a leg of lamb is pretty forgiving. You let it roast in the oven for about 4 hours (depending on the size!) and do make sure to use a meat thermometer to keep an eye on the internal temperature. If there ever was a must have piece of equipment it is a humble thermometer. They’re not expensive and will make all the difference!
Christmas Leg of Lamb with Rosemary and Garlic
If you’re looking for a main course that can take center stage on your Christmas table, a roast leg of lamb is hard to beat. You do a little preparation at the beginning, pop it into the oven and then most of the work is done for you.
For this recipe I use a bone-in leg of lamb and rub it generously with rosemary, thyme, garlic and olive oil. The onions, garlic and herbs underneath the lamb flavor the roasting juices at the same time, which you can use to make a simple gravy afterward.
And because you’re roasting one large piece of meat rather than lots of individual portions, it is also surprisingly practical when you’re cooking Christmas dinner for a group.
What Equipment do You Need?
Below I list all the extra’s and tools you need to create the perfect whole leg of lamb.
- Meat thermometer – this is essential to measure the internal temperature of the meat and make sure it is cooked properly
- A large baking tray that will fit the leg of lamb easily
- Aluminum foil to cover after baking
- Sharp knife
Buying of the Lamb
Getting it exactly right starts with buying the right piece of meat. I have a favorite supplier where I go each year to buy a leg of lamb. If you have a good butcher in your area that you know and trust go there and ask for recommendations. Make sure you get a bone-in lamb leg. That ads so much extra flavor to the dish. If you insist you can of course use a boneless lamb leg but I would recommend one with the bone. You will definitely not be able to find that at the grocery store so make sure to order it in time at your favorite butcher.
Bone-in or Boneless Leg of Lamb?
Both work, but there are a few differences.
A bone-in leg of lamb makes a beautiful centerpiece and is my preferred option for Christmas dinner. The bone also helps protect part of the meat while it roasts. The recipe below is for a bone-in leg of lamb.
A boneless leg of lamb is easier to carve and can often be rolled and tied by your butcher. It tends to cook more quickly, so don’t simply use the cooking time for a bone-in leg.
Whichever you choose, use the internal temperature rather than the clock to decide when your lamb is ready.
Where does the leg of lamb come from?
The leg of lamb is coming from the rear of the lamb and is a bit fattier then – for instance – a lamb chop. It is also perfect if you’re serving a larger crowd. Instead of having to make several smaller pieces you only have to worry about the one piece of meat. It is always roasted whole and like I said, preferably with the bone in.
How Many Servings Does This Recipe Make
Obviously that is depending on the weight and size of your lamb.
A whole bone-in leg usually weighs between 4.5 and 6.5 pounds (2-3 kg). As a general rule, allow around ¾ pound (340 g) of bone-in lamb per person. A 4.5-pound/2 kg leg should comfortably serve around 6 people, especially with several side dishes.
Preparing the Lamb
The best way to prepare the lamb is to start by letting the meat get to room temperature. Take it out of the fridge at least an hour or more and leave it standing on the kitchen counter covered, so it can get to the right temperature.
Start by slicing the fat of the leg in diagonal diamond shapes. You need a good sharp knife to do this. Cut around 1 centimeter deep so you have enough space to add your herbal mixture and rub it in.
The herb mixture is made by chopping the rosemary, thyme and garlic as fine as possible. Mix this with a good amount of olive oil and rub the entire leg with it. Also season generously with pepper and salt.
Now comes the time to place the leg in the oven. Preheat the oven at the highest temperature (usually this is around 230˚C (446˚F) Place the remaining fresh garlic cloves, thyme, rosemary and the onions in a large baking tray and place the lamb on top. Place it in the oven and turn the heat down to 150˚C (300˚F)
How long does a leg of lamb take to cook?
This is probably the question I get asked most, and unfortunately there is no single cooking time that works for every leg of lamb.
The cooking time depends on:
- the weight of the lamb;
- whether it is bone-in or boneless;
- the thickness and shape of the meat;
- the starting temperature of the lamb;
- and your oven.
My approximately 4.4-pound/2 kg bone-in leg of lamb takes around four hours using this slow-roasting method at 300°F/150°C.
But please treat that as a guideline, not a guarantee.
Start checking the lamb before you think it will be ready and use a meat thermometer inserted into the thickest part of the meat, away from the bone.
For food safety, the USDA recommends cooking whole cuts of lamb to a minimum internal temperature of 145°F/63°C, followed by a rest of at least three minutes (which is way too short but more on that below)
Why resting the lamb matters
Once your lamb reaches the desired temperature, take it out of the oven and loosely cover it with aluminum foil.
I like to give a large leg of lamb a good 20–30 minutes of resting time before carving.
Resting gives the juices time to redistribute through the meat rather than immediately running out onto your cutting board. And on Christmas Day it has another advantage: it gives you valuable time to finish the potatoes, vegetables and gravy.
Don’t worry about the lamb getting cold immediately. A large roast stays warm surprisingly well.
FAQ Roasted Leg of Lamb
That is probably the most asked question but also one that is the hardest to answer. The only right way to get the leg just right is by measuring it with a meat thermometer. You insert the meat thermometer in the thickest part of the leg to make sure it measures correctly. It is easiest to use a thermometer that you can insert and that can stay there so you don’t have to open and close the oven all the time.
How long it takes depends entirely on your oven, how thick the leg of lamb is and how heavy. My leg of lamb of roughly 2 kilo at 150˚C (300˚F) took around four hours. Remember that you are making a slow roast. Due to the lower temperature the meat has all the time to develop the most delicious flavors. You can also ask your butcher if he can give you an estimate on how long he thinks the meat is needing. Most good butchers have a pretty good idea.
If you want to use a boneless leg of lamb make sure to adjust the timings as that will cook quicker. if you’re going for boneless you might also ask your butcher to make a filling to go inside.
Serving a roasted leg of lamb and timing it perfectly for your Christmas or Easter dinner can be a bit of a challenge if you’re not entirely sure how long the meat needs. You can prep the entire leg the day before. On the day of your dinner you can cut portions of the meat and heat those (covered with aluminium foil) in an oven at 150˚C. After about 10 minutes the meat should be hot enough and still juicy.
If you have a lot of meat leftover after the dinner, you can slice the rest of the lamb and keep it in the fridge for 1-2 days. It is also delicious as dinner the day after Christmas with some leftover vegetables. Or you can freeze the meat in portions for later use.
For medium rose stick to around 60˚C. (140˚F). You can bake it a little longer if you want but don’t go any higher than 70˚C (158˚F). Remember that it will also keep rising in temperature during the resting process. Also make sure to have the meat rest for at least 30 minutes covered with some foil. Check the table below for easy reference.
| Doneness | Remove from oven around* |
|---|---|
| Medium-rare | 130–135°F / 54–57°C |
| Medium | 135–145°F / 57–63°C |
| Medium-well | 145–150°F / 63–66°C |
A large leg of lamb such as the one here I like to rest for at least 20 to 30 minutes. I read once that you should rest it for half the time it took to roast, but thinking about 4 hours that would mean a 2 hour rest. Bit too long. But 20 to 30 minutes is usually a good amount of time.
A large leg of lamb such as the one here I like to rest for at least 20 to 30 minutes. I read once that you should rest it for half the time it took to roast, but thinking about 4 hours that would mean a 2 hour rest. Bit too long. But 20 to 30 minutes is usually a good amount of time.
What To Serve with Christmas Leg of Lamb
The leg of lamb (either serving this for Easter or for Christmas) combines brilliantly with roasted vegetables, sautéed chayote with bacon, roasted brussels Sprouts or roasted cauliflower. Also delicious with the baked potatoes or the roasted kohlrabi. I think the cranberry sauce is also a great addition for serving the lamb. Or make a gravy out of the juices at the bottom of the roasting pan. That’s pretty delicious too.
As a starter you could go for the salmon tartare or the salmon terrine. Or go for a celeriac soup with mushrooms.
As a dessert you could go for this fantastic Christmas trifle or the chocolate chip surprise. Or have a look here for all the Christmas recipes.
Christmas Leg of Lamb with Rosemary and Garlic
Ingredients
- 2 kgs leg of lamb with bone
- 1 bunch rosemary
- 1 bunch thyme
- 1 head garlic whole head
- 2 onions roughly cut
- olive oil
- pepper and salt
Equipment
- Meat thermometer
- Large baking tray
- Aluminum foil
Instructions
- Cut the lamb on the fatty side. Make incisions of around a centimeter deep in diamant shape. Remove the needles from a few rosemary twigs and thyme and cut them finely. Chop a few of the garlic cloves as well. Rub the lamb well with olive oil and the herb mixture. Make sure you press it inside the cuts. Sprinkle liberally with salt and pepper.
- Preheat the oven on full temperature (usually around 230˚C/450˚F) Take the rest of the garlic apart into separate cloves and smash them on the side with a large knife. Spread the onion, a part of the garlic, thyme and rosemary across the bottom of a baking tray. Place the leg of lamb on top and sprinkle with the rest of the garlic and the herbs. Place in the oven and lower the temperature immediately to 150˚C/300˚F.
- Use the thermometer as that is the only way to be sure that your meat has reached the desired temperature. Medium pink is around 63˚C/145˚F. You can keep it in the oven longer but never go further than 70˚C/170˚F. Remember that it will continue cooking once out of the oven too!
- Roast the lamb for about four hours in the oven and check regularly to make sure the top doesn't get too brown. Baste it from time to time with the cooking liquids from the baking tray. If it gets too dark but is not cooked properly yet, cover the lamb with aluminium foil and place back in the oven
- Take it out of the oven once it reaches the right temperature and wrap in aluminium foil. Place a towel over the foil to keep it warm and leave to rest at least for half an hour in a warm spot. Cut at the table with a large and sharp knife and serve with roasted vegetables and baked potatoes
Notes
Storing leftover roast lamb
Let leftover lamb cool, then refrigerate it in an airtight container. Use the leftovers within a few days. I prefer reheating sliced lamb gently rather than putting the entire roast back into a hot oven. Adding a little of the leftover gravy or cooking juices helps prevent the meat from drying out. Leftover lamb is also delicious cold in sandwiches and salads.Nutrition Information per portion:
Disclaimer:
The nutritional values above are calculated per portion. The details are based on standard nutritional tables and do not constitute a professional nutritional advice.
I just had some slow cooker lamb neck 🙂 And lamb leg is also one of my favourites! Garlic, thyme and rosemary are perfect for the lamb.
Ah this would be great in the slow cooker too! Although this one probably doesn’t fit. Lol. But great idea for a lamb neck. I tend to make pulled pork in the slow cooker always!