Prep the Lamb: Preheat your oven to 400°F (200°C). Trim the racks of lamb of excess fat.

Make the Mustard Herb Mix: In a small bowl, combine the Dijon mustard, minced garlic, finely chopped shallot, minced rosemary, and thyme leaves, along with the salt and pepper, to create a delicious paste. Mix well.

Sear the Lamb: Heat a tablespoon of clarified butter in a large, oven-proof skillet over high heat. Add the lamb racks, fat side down, and sear until each side is golden brown, about 2-3 minutes. Remove from heat and let them cool slightly.

Apply the Mustard Herb Mix: With the racks slightly cooled, brush a generous amount of your mustard and herb mixture over the fat side and meaty parts of the racks.

Roast: Transfer the racks back to the skillet or into a roasting pan, mustard side up, and place them in the preheated oven. Roast 20-25 minutes for a medium-rare temperature (135F), or adjust according to your preferred doneness.

Broil for Perfection: For a golden and slightly crispy crust, switch your oven to broil and place the lamb under the broiler for 2-3 minutes, keeping a close eye to avoid burning.

Rest and Serve: After removing the lamb from the oven, let it rest for about 10 minutes. This step is crucial for redistributing the juices. Slice between the ribs and serve.