Prepare the Roasted Garlic Confit: Preheat your oven to 300°F (150°C). In a baking dish, combine the garlic cloves, olive oil, thyme, rosemary, salt, and pepper. Ensure the garlic is mostly submerged in oil. Cover the dish with foil and roast in the oven for about 1 hour, or until the garlic is soft and golden brown. Remove from the oven and let it cool. Once cooled, store in an airtight container in the refrigerator.

Prepare the Smoked Leek Compound Butter: In a skillet over medium heat, add a splash of olive oil and the chopped leeks. Sauté until softened and translucent, about 5-7 minutes. Allow to cool. In a bowl, combine the softened butter, sautéed leeks, smoked paprika, garlic powder, salt, pepper, and parsley. Mix until well combined. Place the compound butter on a piece of parchment paper and roll into a log. Twist the ends to secure and refrigerate until firm.

Prepare the Sage-Crusted Lamb Rack: Preheat your oven to 400°F (200°C). Season the lamb rack with salt and pepper. Brush the Dijon mustard over the meat. In a bowl, mix the breadcrumbs, chopped sage, salt, and pepper. Press this mixture onto the mustard-coated lamb rack to create an even crust. Heat olive oil in a large oven-safe skillet over medium-high heat. Once hot, sear the lamb rack for 2-3 minutes on each side until browned. Transfer the skillet to the preheated oven and roast for 15-20 minutes for medium-rare, or until a meat thermometer reads 130°F (54°C). Adjust the time based on your preferred doneness.

Serve: Remove the lamb from the oven and let it rest for about 10 minutes before slicing into individual chops. Serve with a generous dollop of the smoked leek compound butter on top of the warm lamb, alongside the roasted garlic confit.