For the lamb: Place an oven rack in the center of the oven. Preheat the oven to 425 degrees F. Place a grill pan over medium-high heat or preheat a gas or charcoal grill.
Drizzle the olive oil on both sides of the lamb. Season with salt, pepper and herbs de Provence. Grill the lamb for 5 minutes on each side until brown. Place the lamb in a shallow roasting pan or baking sheet and roast for 25 minutes for medium-rare. Allow the lamb to rest for 10 minutes before slicing.
For the sauce: In a small bowl, combine the creme fraiche, honey, cumin, and mint. Add the mascarpone cheese and stir until just combined. Season with salt and pepper, to taste.
Cut the lamb between the bones into individual chops and serve with the sauce.
The lamb can also be browned for 4 to 5 minutes each side in a large skillet over high heat.