Garlic Herb Roasted Leg Of Lamb
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There’s something wildly satisfying about roasting a leg of lamb. It feels fancy, smells incredible, and instantly turns any dinner into an event. This Garlic Herb Roasted Leg of Lamb is coated in a bold rosemary-garlic-mustard rub, slow roasted to juicy perfection, and finished off with a rich, optional pan gravy, because why not go all in?
My No-Fail Roasted Leg Of Lamb
Growing up, lamb was always an Easter thing in our house. My mom makes it every year for my dad, the resident lamb lover, while the rest of us politely chewed and reached for extra bread. I still remember the smell, though, rosemary, garlic, wine, all wafting from the oven as that leg of lamb slow roasted for hours until it was unbelievably tender and juicy.
These days, it’s my turn. I married a man who also insists on lamb for Easter (tradition is tradition), and this is my go-to recipe. Garlic-heavy, just how I like it, with a good rub, a bit of mustard, and maybe a nod to my mom’s red wine trick. It’s the one lamb dish I’ll gladly eat once or twice a year, and actually enjoy.
Before You Start
After decades of roasting everything from pork to poultry, I can tell you this: leg of lamb is one of the most rewarding cuts to master. It’s naturally tender, packed with tons of flavor, and only needs a few smart techniques to really shine.
Choose the Right Cut
- This recipe is for a bone-in leg of lamb, which has more flavor and stays juicy as it roasts. Look for one around 4-5 pounds, but really it depends on how many people you’re serving. Aim for ¾ to 1 pound per person if you’re using bone-in lamb or ½ pound per person for boneless lamb.
- Trim wisely. Don’t remove all the fat because a little fat = flavor and moisture. Just trim the thickets parts and any silver skin.
- Season deep! Don’t just smear the rub on the surface, make incisions and work that garlic-herb mixture into the meat. This step takes an extra minute but gives you massive payoff in flavor.
Temperature Matters
- Room temperature = even roasting! Let the lamb sit out for 30 minutes before roasting. Cold meat straight from the fridge cooks unevenly, and you risk drying it out before it’s even done.
- For medium-rare, aim for 135°F internal temp; for medium, go for 145°F. Use a meat thermometer and trust it. Lamb can go from perfect to overcooked quickly.
- Don’t skip the rest! Always let your roast rest for at least 20 minutes before carving. This locks in the juices and keeps it beautifully tender.
The Gravy is Everything!
Use the drippings to make the quick red wine pan gravy. It really does add incredible depth to the roast and only takes just a couple minutes on the stovetop, totally worth it!
In a small bowl, whisk together the grainy Dijon mustard, olive oil, minced garlic, rosemary, salt and pepper. It should be a thick and fragrant, almost like a paste. Grainy mustard not only helps everything stick but it adds depth and a little tang that balances the richness of the lamb.
Start by trimming off excess fat or silver skin, but don’t go overboard, some fat is your friend here. Then, using a sharp knife, make small incisions all over the meat, about 1 inch long and ½ inch deep.
These little pockets let the rub get right into the meat instead of just sitting on the surface, so don’t skip them!
Massage the garlic herb mixture all over the lamb and make sure to work it into every incision. Now, let it sit at room temperature for about 30 minutes, this should take the chill of and helps it roast evenly.
Tip: You can even prep it earlier in the day and refrigerate, just bring it back to room temp before roasting.
Preheat your oven to 425°F and place the lamb on a rack in a roasting pan. Pour chicken broth or water into the pan to keep things moist and build a flavor base for gravy later.
- Start hot, roast at 425°F for 30 minutes to get that golden crust.
- Then reduce to 325°F and continue roasting until done.
- For medium-rare: roast to 135°F internal temperature. For medium: aim for 145°F.
- Use a meat thermometer, there’s no guessing when it comes to roasting lamb right.
Once the lamb hits your desired temp, take it out and let it rest for at least 20 minutes before slicing. This step is very important, it lets the juices redistribute so they don’t run all over your cutting board the second you slice in. I usually cover mine with aluminum foil.
For me this isn’t optional, and I highly recommend you make this as well. While the lamb rests, pour the lamb drippings in a small saucepan and place it over medium heat. Add the wine and then whisk in broth with a bit of flour to thicken the gravy. Taste it and season it to your liking. It only takes a few minutes and totally worth it.
Lamb Doneness Guide – Know Your Temps Before You Carve
| Rare | 125°F (52°C) | very pink, soft texture |
| Medium-rare | 130–135°F (54–57°C) | ender and juicy with a warm pink center (most popular) |
| Medium | 140–145°F (60–63°C) | slightly firmer with less pink |
| Well done | 155–160°F+ (68–71°C) | fully cooked through, little to no pink, can be drier |
What to Serve with Lamb
This roast is the centerpiece, so let it shine, but it definitely deserves some solid support on the plate. Here’s how I like to serve it:
- Carve against the grain into thin slices.
- Spoon that rich pan gravy over the top (or let everyone fight over it at the table).
- Serve hot, preferable with something to mop up all that goodness.
Here are my idea of perfect sides:
Mashed Potatoes
Roasted Baby Potatoes
Lemon Orzo with Asparagus
No Knead Bread
Frequently Asked Questions
Can I use boneless leg of lamb instead?
Yes! Boneless works great, just know it cooks a bit faster and may not be quite as juicy as bone-in. Tie it up with kitchen twine so it roasts evenly and aim for the same internal temps.
Do I really have to let it rest before carving?
Yes, yes, a thousand times yes. At least 20 minutes. If you slice too soon, all those lovely juices will run out onto your cutting board instead of staying in the meat. You’ve come this far, give it a minute.
Can I prep this ahead of time?
Definitely. You can make the rub and season the lamb up to a day in advance, just wrap it up and refrigerate. Bring it to room temp before roasting so it cooks evenly.
Is the pan gravy really necessary?
Not necessary, but highly recommended. It’s fast, uses the drippings you already have, and turns an already impressive roast into something next-level. Plus, it’s a great excuse to mop your plate with bread.
Can I freeze the leftovers?
Absolutely. Lamb holds up well in the freezer. Slice it first, then store in an airtight container or freezer bag for up to 3 months. When you’re ready, reheat gently, low oven or stovetop with a splash of broth to keep it juicy. Bonus: leftover lamb makes killer sandwiches or wraps.
Try These Next
- Easy Kofta (Beef Or Lamb)
- Lamb Souvlaki
- Lamb Korma
- Braised Lamb Shanks
- Slow Roast Leg of Lamb
- Herb Crusted Rack Of Lamb
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Garlic Herb Roasted Leg Of Lamb
Video
Ingredients
- 4-5 pound bone-in leg of lamb
- 6 cloves garlic (minced)
- 1 tablespoon dried rosemary
- 2 tablespoons Dijon grainy mustard
- 2 tablespoons olive oil
- salt and pepper ( to taste)
- 1 cup chicken broth (or water)
Gravy (Optional)
- ½ cup dry red wine
- 1 cup chicken broth
- 1 tablespoon all-purpose flour
Before You Begin! If you make this, please leave a review and rating letting us know how you liked this recipe! This helps our business thrive & continue providing free recipes.
Instructions
- In a small bowl whisk together the mustard, garlic, rosemary, olive oil, salt and pepper.
- Trim off any excess fat that may lie beneath the fell, but not all, you might want to leave some to enrich the flavor of the meat and/or gravy. Make incisions with a knife that are about 1 inch long and ½ inch deep.
- Apply the rub to the leg of lamb evenly, making sure to fill the incisions with some of the rub. Let the leg of lamb sit at room temperature for about half hour.
- Preheat oven to 425℉. You'll need a large roasting pan fitted with a rack, pour the broth in the bottom of the pan and transfer leg to the pan. Roast it for about 30 minutes, then reduce temperature to 325℉ and continue roasting until cooked to your liking. For medium rare, you want the temperature to be 135℉, for more well done, you need it to be 160℉, this will take a couple hours.
- Let the lamb rest for 20 minutes before carving it.
- While the lamb rests, pour the lamb drippings in a small saucepan and place it over medium heat. Add the wine and then whisk in broth with the tablespoon of flour to thicken the gravy. Cook for 1 or 2 minutes until the gravy has thickened. Taste it and season it to your liking. Pour into a gravy bowl and serve with lamb.
Notes
- Leg of lamb: This recipe uses a bone-in leg, which gives more flavor and helps keep the meat juicy. A 4–5 lb leg will serve about 4–6 people depending on appetites and sides.
- Grainy mustard: Dijon is the base of the rub, it adds tang and helps the garlic and herbs stick. Don’t skip it!
- Garlic & rosemary: Classic combo. Use fresh rosemary if you have it (1 tablespoon chopped = 1 teaspoon dried).
- Roasting temps: Start high at 425°F for color, then reduce to 325°F to finish. Aim for 135°F for medium-rare or 145°F for medium.
- Let it rest: This step is non-negotiable. At least 20 minutes so the juices redistribute and the meat stays tender.
- Optional gravy: Quick and so worth it. Just whisk in red wine and broth with a little flour right in the roasting pan, zero waste, maximum flavor.
- Make ahead: Rub the lamb and refrigerate up to 24 hours in advance. Bring to room temp before roasting.
Nutrition Information
Notice: Nutrition is auto-calculated for your convenience. Where relevant, we recommend using your own nutrition calculations.
