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A gorgeous boneless leg of lamb recipe, studded with rosemary sprigs & garlic, and roasted to perfection. I show you how to roast lamb for the perfect Sunday dinner!
My husband hates lamb. There, I said it. This of course, is crazy to me. I grew up in New Zealand. Yup – 3 million people, 20 million sheep. We ate a lot of lamb!
Lamb, for me, is a memory-invoker. The smell of roast lamb in the oven takes me right back to Sunday dinners at home, sometimes with grandparents, sometimes not, but ALWAYS with mint sauce, or mint jelly.
It is my all-time favorite meat – so my heart was broken when my husband announced that even the smell of it cooking makes him gag. He went out of town, so I figured this is my perfect opportunity to have exactly what I want. Plus, I am missing my Mum, (the all time greatest roaster of lamb).
How long does to take to cook boneless lamb?
Roast for around 15-20 minutes per pound. So, for a 4lb roast – 60 minutes. But you’ll want to check the temperature so you know you got it perfectly cooked!
What temperature should boneless leg of lamb be cooked to?
I cook mine to medium, (which is optimal lamb temp) which is about 150 degrees F.
| Doneness | Remove from Oven | Final Temp |
| Medium Rare | 135°F | 145°F |
| Medium | 150°F | 160°F |
| Well Done | 160°F | 170°F |
What kind of lamb should I buy?
I recommend using a quality leg of New Zealand lamb. Of course, you can buy lamb from many countries, including the USA – but in (somewhat biased, I suppose) opinion, it has a better flavor. I like the boneless ones, because they’re super easy to carve!
What to serve with Roast Lamb
This yummy roast lamb pairs really well with some roasted veggies. You can throw them in with the lamb, and dinner will be a one pan dish! Good options are potatoes, pumpkin, or sweet potato.
How to Roast Lamb perfectly
Preheat your oven to 450 degrees F.
Start by rinsing the lamb under cold water.
Make a series of deep knife cuts into the top. (see pictures below for a better idea of what I’m talking about).
Stud the roast with the garlic and rosemary randomly, pushing the pieces in as far as possible. This is going to flavor the meat as it cooks, so you’ll want it to “go deep”.
Season with salt and pepper, and roast in the oven for 30 minutes.
After 30 minutes, turn the oven down to 350 degrees F.
Roast for around 15-20 minutes per pound. So, for a 4lb roast – 60 minutes. But you’ll want to check the temperature so you know you got it perfectly cooked!
I cook mine to medium, (which is optimal lamb temp) which is about 150 degrees F. If you like your meat a bit more medium-well to well done, roast for an extra 10 minutes or so.
Rest
Remove from the oven, and rest tented in foil for about 10 minutes before carving.
Cut against the grain.
How to make a pan gravy
Make a flavorsome gravy made with a base of fat/drippings from roasting lamb.
- Remove all but 2 Tbs of drippings from the pan.
- Place the roasting pan on your stove, and heat to medium-high.
- Whisk in about 2 Tbs flour, then whisk in the hot stock.
- Season with salt, pepper and add some fresh or dried rosemary.
- Simmer, mixing constantly until thickened.
- Test for seasoning and add more if needed.
- You have the option of making a pan gravy, using the drippings, flour, some water or stock and some salt/pepper. Or you could just do the mint jelly thing, and call it GOOD!
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Boneless Leg of Lamb Recipe
Ingredients
- 4 lb lamb ((boneless))
- 2 inch sprigs fresh rosemary (cut into 1/2pieces)
- 3 cloves garlic (peeled, and chopped into thick slivers)
- Salt and pepper
Directions
- Preheat your oven to 450 degrees F.
- Start by rinsing the lamb under cold water.
- Make a series of deep knife cuts into the top. (see picture for a better idea of what I’m talking about).
- Stud the roast with the garlic and rosemary randomly, pushing the pieces in as far as possible. This is going to flavor the meat as it cooks, so you’ll want it to “go deep”.
- Season with salt and pepper, and roast in the oven for 30 minutes.
- After 30 minutes, turn the oven down to 350 degrees F.
- Roast for around 15-20 minutes per pound. So, for a 4lb roast – 60 minutes. But you'll want to check the temperature so you know you got it perfectly cooked!
- I cook mine to medium, (which is optimal lamb temp) which is about 150 degrees F. If you like your meat a bit more medium-well to well done, roast for an extra 10 minutes or so.
- Remove from the oven, and rest tented in foil for about 10 minutes before carving.
How to make a pan gravy
- Remove all but 2 Tbs of drippings from the pan.
- Place the roasting pan on your stove, and heat to medium-high.
- Whisk in about 2 Tbs flour, then whisk in the hot stock.
- Season with salt, pepper and add some fresh or dried rosemary.
- Simmer, mixing constantly until thickened.
- Test for seasoning and add more if needed.
Nutrition Facts
Disclaimer
Nutritional information is an estimate and provided to you as a courtesy. You should calculate the nutritional information with the actual ingredients used in your recipe using your preferred nutrition calculator.
Anita Tanner says
Just what we had for dinner last night. Rosemary and garlic are a must with lamb! Thanks for sharing our good old NZ lamb with the world. We, like you are biased as well but NZ lamb can’t be beaten in my opinion. Keep up your cool recipes Kylee.
Jan & Stan says
I so wish I had been there to share it with you. We are having roast lamb one night this week I think. It is yummy.