An hour before you start roasting the lamb, line a large rimmed baking sheet with foil and spray it with olive oil spray.
Place the rack of lamb on the prepared baking sheet, fat side up. Score the fat by making small shallow slits, 1 inch apart.
Liberally spray both sides of the lamb with olive oil and sprinkle with the salt, pepper, garlic powder, rosemary and thyme. Allow the seasoned rack of lamb to come to room temperature.
20 minutes before you plan on roasting the lamb, preheat the oven to 425 degrees F.
Roast the rack of lamb in the preheated oven until an instant-read thermometer inserted into the thickets part of the meat (and not touching the bone) reads 135 degrees F (medium-rare), about 25 minutes.
Remove the roasted rack of lamb from the oven. Transfer to a cutting board. Cover with foil and allow to rest for 10 minutes.
Using a sharp chef's knife, cut into individual lamb ribs by slicing between the bones. Serve immediately.
Consuming undercooked meat may increase your risk of foodborne illness. I always cook lamb and beef steaks, chops and roasts to medium-rare. But you should make your own decision.Nutrition info is based on fitday.com, assuming 6 oz with bone, lean and fat eaten.