Whisk together the marinade in a bowl by combining Dijon mustard, minced garlic, fresh rosemary, thyme, olive oil, lemon juice, salt, and pepper. This flavorful mixture will coat the lamb beautifully.

Rub the marinade generously over the rack of lamb, ensuring every nook and cranny is covered. Let it marinate for at least 30 minutes or up to overnight in the fridge for maximum flavor.

Preheat your oven to 400°F (200°C), allowing it to reach the right temperature while the lamb marinates. This step is crucial for an even roast.

Heat olive oil in an oven-safe skillet over medium-high heat. Sear each side of the rack for about 3–4 minutes until it's beautifully browned, adding depth to the flavor.

Transfer the skillet to your preheated oven and roast the rack of lamb for about 20–25 minutes. You’re aiming for an internal temperature of 125°F (52°C) for that perfect medium-rare finish.

Let the lamb rest for 10 minutes under foil to keep it warm and juicy before slicing into chops and serving. This step allows the juices to redistribute, enhancing tenderness.