Have Your Butcher Trim the racks, exposing the bone. Remove the outer layer of fat and discard. Lay the racks in a glass dish and sprinkle with 1 tablespoon oil, 1/4 cup vinegar, garlic, coriander, salt and pepper. Cover and let stand at room temperature for 1 hour. Preheat oven to 450F. Pat racks dry and place fat side up in a roasting pan. Place in oven for 10 minutes, reduce heat to 350F and continue to roast another 15 minutes for medium rare, 18 to 20 minutes for medium. Meanwhile, place the bacon in a 10-inch skillet over medium heat and cook 3 to 4 minutes. Set the skillet aside. Remove the lamb from the oven and pour out the fat. Add chicken broth and stir to dissolve and scrape up any brown bits that have stuck to the bottom of the pan. Pour liquid into the skillet with the bacon. When it's time to put dinner on the table, cut the racks into chops and arrange them on a platter. Pour any juices from the lamb into the saucepan. Place the skillet over high heat, bring to a boil and add the mustard. Remove from the heat, beat in the rest of the oil and pour the sauce over the lamb.