For the lamb, brush the meat with the oil and season well with salt and freshly ground black pepper. Heat an ovenproof griddle pan until smoking, then chargrill the lamb for 3-4 minutes, or until golden-brown. Turn the lamb over, add the balsamic vinegar and cook for 3-4 minutes, or until the vinegar has reduced to a sticky consistency and the lamb is cooked to your liking.
For the courgette, place all of the courgette ingredients in a bowl and toss well to coat. Allow to marinate for ten minutes.
To serve, arrange the courgette ribbons on a serving plate. Slice the lamb and place on top of the courgette.