Preheat the oven to 200c (390F). Place the oil, honey, vinegar, mint, salt and pepper in a large non-metallic bowl. Add the lamb and toss to coat. Allow to marinate for 20 minutes.
Place the potatoes in a metal baking dish with the extra oil and toss to coat. Reserving the marinade, place the lamb on a wire rack above the potatoes and cook for 20 minutes or until the lamb is cooked to your liking and the potatoes are tender and golden. Place the marinade in a small saucepan over medium heat and simmer for 2-3 minutes. Serve with the lamb and potatoes.