In a large Ziplock bag, mix the salt, spices, minced rosemary, garlic, and olive oil.
Place the lamb racks into the bag.
Squeeze out the air and zip the bag. Massage it slightly so that olive oil, garlic, and all other spices are evenly distributed.
Marinate the lamb for at least an hour, or overnight.
Preheat the oven to 375°F (190°C).
Place the lamb racks on a baking sheet lined with foil.
Roast for 20-30 minutes depending how you like it done. The internal temperature should reach at least 130-140°F for medium rare.
Broil for 2-3 minutes to add a little char before taking it out.
Cover with foil and rest for about 5 minutes before serving.