Cooking a leg of lamb on the BBQ can be a delightful experience, offering a surprising diversity in flavour and texture depending on the method you choose. Today, we’ll explore two distinct approaches: a super fast method using a boneless, butterflied leg of lamb, and a super slow method involving a smoked, low and slow bone-in leg of lamb. Each technique brings out unique qualities in the meat, ensuring a memorable meal for any occasion and timeframe!

Method 1: Super Fast – Boneless, Butterflied Leg of Lamb

The boneless, butterflied leg of lamb is perfect for those who want a quick yet flavourful BBQ experience. By removing the bone and flattening the meat, you increase the surface area, allowing for faster cooking and more even seasoning. If you’re not confident on how to prepare boneless leg of lamb, your butcher should happily oblige. This method is ideal for a weeknight dinner or a spontaneous BBQ gathering.

Step-by-Step Guide

Ingredients:

• 1 boneless, butterflied leg of lamb (approximately 1.5-2 kg)
• 12 cloves of garlic, minced
• 6 or so anchovy fillets, finely chopped
• 4 tablespoons fresh rosemary, chopped
• 4 tablespoons fresh thyme, chopped
• 1 lemon, zested and juiced
• 6 tablespoons olive oil
• Salt and pepper to taste

Instructions:

Preparation

• Lay the butterflied leg of lamb flat on a large cutting board. Trim any excess fat and pat the meat dry with paper towels.
• In a small bowl, combine the minced garlic, chopped rosemary, thyme, lemon zest, lemon juice, olive oil, salt, and pepper. Mix well to form a marinade. Alternatively, you could pound all of the marinade ingredients in a pestle and mortar, which produces even more flavourful results.

Marinating

• Rub the marinade all over the lamb, ensuring it is evenly coated. For best results, let the lamb marinate for at least 1 hour at room temperature, or refrigerate for up to 24 hours for a more intense flavour.

Preheating the BBQ

• Preheat your BBQ to high heat (around 230-260°C). If using a gas grill, turn all burners to high. For a charcoal grill, ensure the coals are white-hot and spread evenly (hold your hand a few centimetres above the coals – if you need to pull away in two to four seconds, it’s the right level of heat). 

Grilling

• Place the lamb on the grill, skin-side down. Sear for 4-5 minutes until nicely charred.
• Flip the lamb and continue to grill for another 4-5 minutes on the other side.
• Reduce the heat to medium (around 180-200°C) and continue to cook for an additional 10-15 minutes, flipping occasionally, until the internal temperature reaches 60°C for medium-rare. If you’re grilling over charcoal, the heat will have reduced to medium naturally, but if it feels too hot, move the lamb to a position over indirect heat.

Resting

• Remove the lamb from the grill and let it rest for 10 minutes. This allows the juices to redistribute, ensuring a moist and tender result.

Serving

• Slice the lamb against the grain and serve with your favourite sides. A fresh green salad or grilled courgettes and aubergine should complement the lamb beautifully. A salsa verde feels almost obligatory here.

Read: BBQ vegetable recipes from Daniel Watkins, Acme Fire Cult

Method 2: Super Slow – Smoked, Low and Slow Bone-In Leg of Lamb

For those who enjoy a leisurely cooking process and the deep, smoky flavours that come with it, the smoked, low and slow bone-in leg of lamb is the way to go. This method requires patience but rewards you with incredibly tender, flavourful meat that falls off the bone.

Step-by-Step Guide

Ingredients:

• 1 bone-in leg of lamb (approximately 2.5-3 kg)
• 12 cloves of garlic, sliced
• 6 tablespoons fresh rosemary, chopped
• 6 tablespoons fresh thyme, chopped
• 3 tablespoon smoked paprika
• 2 tablespoon ground cumin
• 6 tablespoon olive oil
• Salt and pepper to taste
• Wood chips (hickory or applewood recommended)

Instructions:

Preparation:

• Make small incisions all over the leg of lamb and insert the garlic slices into the cuts.
• In a small bowl, combine the chopped rosemary, thyme, smoked paprika, ground cumin, olive oil, salt, and pepper. Rub this mixture all over the lamb, ensuring it is well coated.

Setting Up the Smoker:

• Preheat your smoker to 110-120°C. If using a charcoal smoker, light the coals and let them burn until they are covered with white ash. Add wood chips to the smoker box or directly onto the coals for a smoky flavour. 

Alternatively, you can smoke on a charcoal grill:

• Indirect Heat Setup: Arrange the charcoal on one side of the grill to create a two-zone cooking area. This allows you to cook the lamb with indirect heat, preventing it from burning and ensuring a slow, even cook.
• Adding Wood Chips: Soak wood chips in water for at least 30 minutes before adding them to the coals. This helps them smoulder and produce smoke rather than burning up quickly. Place a handful of soaked wood chips directly on the hot coals.
• Maintaining Temperature: Adjust the air vents on your grill to control the temperature. Open vents increase the temperature, while closing them reduces it. Aim to keep the grill temperature steady at 110-120°C.
• Placing the Lamb: Place the lamb on the grill grate over the side without coals (indirect heat). Close the lid and let the smoke work its magic.

Smoking

• Smoke the lamb for approximately 4-5 hours, maintaining a consistent temperature. Add more charcoal and wood chips as needed to keep the smoke going and the temperature steady.
• Check the internal temperature of the lamb periodically. You’re aiming for an internal temperature of 93°C for fall-off-the-bone tenderness.

Basting (Optional)

• Every hour, you can baste the lamb with a mixture of olive oil, lemon juice, and herbs to keep it moist and add extra flavour.

Resting

• Once the lamb reaches the desired internal temperature, remove it from the smoker and wrap it in aluminium foil. Let it rest for at least 30 minutes. This resting period is crucial for the juices to redistribute and the meat to become even more tender.

Serving

Carve the lamb, slicing against the grain. The meat should be incredibly tender and infused with a rich, smoky flavour. Serve with some grilled flatbreads and a mint yoghurt sauce for a classic pairing.

The Bottom Line

Whether you opt for the quick and convenient boneless, butterflied leg of lamb or the indulgent, slow-cooked smoked bone-in leg of lamb, both methods offer a unique and delicious BBQ experience. 

The fast method is perfect for those short on time but still keen on serving up a flavourful, clearly grilled, medium-rare meat, while the slow method is ideal for a relaxed weekend barbie with plenty of beers, allowing you to savour the process and the results – not to mention the classic gathered-around-the-grill chat!

And if you’ve got any leftover lamb, you’ll find some fantastic suggestions for re-deploying it here. So, when can we expect our invite over to yours for dinner?