01 - In a small bowl, combine minced garlic, chopped rosemary, fresh thyme leaves, Dijon mustard, olive oil, kosher salt, and black pepper. Mix thoroughly to form a cohesive paste.
02 - Pat the rack of lamb completely dry using paper towels. Rub the prepared marinade evenly over all surfaces of the lamb, ensuring thorough coverage.
03 - Place the coated lamb in a shallow dish or resealable plastic bag. Refrigerate for at least 1 hour, or up to overnight for enhanced flavor penetration.
04 - Remove the lamb from refrigeration 30 minutes prior to cooking to allow it to reach room temperature. Preheat the oven to 425°F.
05 - Heat 1 tablespoon olive oil in a large ovenproof skillet over medium-high heat. Sear the rack of lamb for 2-3 minutes per side until a golden-brown crust forms.
06 - Transfer the skillet to the preheated oven. Roast for 15-20 minutes for medium-rare (internal temperature 125-130°F), adjusting time to your preferred doneness.
07 - Remove the lamb from the oven and tent loosely with aluminum foil. Allow to rest for 10 minutes before slicing into individual chops to preserve juices.
08 - Slice the rested rack between the bones into individual chops. Sprinkle with flaky sea salt immediately before serving, if desired.