Season the meat with salt and pepper. Mix together the oil and mustard, then slather all over the rack to coat well. Mix together the breadcrumbs, cheese and herbs, then pack the mixture onto the lamb rack.
Place the lamb on a rack, bones arching upwards, in a roasting pan just large enough to hold it and place in oven. Roast until the meat is done to your liking. 20 minutes will give you medium-rare meat. Let the meat rest out of the oven 10 minutes before carving.