Grilling an Aussie leg of lamb roast is just as straightforward as roasting it in the oven. These tips and a simple rub will help you get a flavorful, tender roast every time.
Disclosure: True Aussie Lamb sponsored this post. Opinions are my own.

For the best results, trim the fat cap to about 1/8–1/4 inch. A thin layer of fat adds flavor, but if it’s too thick the rub won’t penetrate the meat and the seasoning won’t develop a nice crust.

Choose or mix a rub. I use salt, black pepper, garlic powder and onion powder as a base on most meats. Aussie lamb has a natural sweetness that holds up well to bolder flavors, so smoked paprika and cumin add a warm, savory note. Dried rosemary highlights the lamb’s sweetness, cayenne adds heat to taste, and a touch of raw sugar helps promote a golden crust.

Cook the lamb over indirect heat to prevent the rub from burning and to ensure even cooking. On a gas grill, light only part of the burners and place the roast over the unlit side. On a charcoal grill, push the coals to one side and cook the roast on the opposite side. Ceramic cookers or pellet grills are ideal for boneless roasts because a diffuser plate shields the meat while maintaining consistent heat.
I prefer a hot-and-fast approach for a leg roast: set the grill to 350–375°F. At that temperature, a 5-pound boneless roast typically finishes in about 2 hours. Aim for an internal temperature of 135°F for a medium result after resting. If you like it rarer, remove the roast around 125°F; for firmer doneness, cook another 5–15°F. Expect the temperature to rise roughly 5°F while the meat rests.

When the lamb’s internal temperature reaches 80–90°F, you’ll have about 30 minutes remaining. This is a good time to add vegetables—toss rainbow carrots in olive oil, salt and pepper, and place them on the grill so they finish with the roast.

When the roast reaches your target temperature, transfer it to a pan and tent loosely with foil. Resting is essential: it lets the juices redistribute, yielding a juicier, more tender slice.

Rest the roast for 15–30 minutes, then slice and serve with the roasted carrots. Finish with fresh herbs for color and brightness.

More lamb recipes
- Lamb Shoulder Chops with Cherry Port Wine Sauce
- Smoked Lamb Sliders with Carolina Barbecue Sauce
- Grilled Lamb Chops
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Grilled Aussie Leg of Lamb Roast
Ingredients
- 5 pound Aussie Boneless Leg of Lamb Roast
Smoked Paprika Rub
- 1 tablespoon raw sugar
- 1 teaspoon kosher salt
- 1 teaspoon black pepper
- 1 teaspoon smoked paprika
- 1 teaspoon garlic powder
- 1 teaspoon rosemary, dried
- 1 teaspoon onion powder
- 1 teaspoon cumin
- 1/2 teaspoon cayenne pepper
Roasted Carrots
- 1 bunch rainbow carrots
- olive oil
- salt
- pepper
Instructions
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Heat the grill to 350–375°F and set up an indirect heat zone.
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Trim the fat so it is no thicker than 1/8–1/4 inch.
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Combine the rub ingredients and rub evenly over the meat.
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Place the lamb on the grill over indirect heat and cook for about 2 hours, monitoring internal temperature.
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Toss the carrots with olive oil, salt and pepper.
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When the lamb reaches 80–90°F (about 1½ hours in), add the carrots to the grill so they finish with the roast.
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Continue cooking until the lamb’s internal temperature reaches about 135°F for medium. Remove, cover with foil and rest 15–30 minutes.
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When the carrots are tender, remove them from the grill and serve alongside the sliced lamb.
Nutrition
Nutrition information is automatically calculated and should be used as an approximation.