Preheat oven to 425°F. Season the racks with salt and pepper and set aside.
Place all the glaze ingredients in a small saucepan and bring to boil. Reduce heat and simmer until mixture thickens and becomes glossy, about 10-15 minutes.
Heat a large ovenproof pan to medium high and coat pan with oil. Sear the lamb racks for 2-3 minutes each side to brown, then tip any excess fat from pan. Brush with a little of the glaze, place in the oven and roast for 10-12 minutes, or until medium-rare and it reaches an internal temperature of 130°F. Transfer to a warm plate, cover loosely with foil and let rest for 5-10 minutes before slicing; or place uncut rack in the refrigerator and serve cold the next day. (Lamb will stay moist and fresh if sliced just before serving.)
To make salad, wash and dry the salad greens well and place in a large bowl. Combine the lemon juice and oil and toss through the leaves with the Parmesan cheese. Arrange salad on a platter and place lamb on top. Remove the rosemary and drizzle glaze over all. Serve with crusty Italian bread.
