Herb-crusted lamb with a gratin of leeks and brussels sprouts

Method

1. Preheat the oven to 200°C/fan180°C/gas 6. Rub the lamb with a little olive oil, then rub all over with the garlic clove. Season well.
2. Blanch the leeks and sprouts in boiling water for a couple of minutes. Drain and refresh under cold water, then drain again.
3. Melt the butter in a saucepan over a low heat, then stir in the flour and cook for a couple of minutes. Gradually add the milk, stirring constantly, to form a smooth sauce. Season well with nutmeg, salt and pepper, then add most of the cheese.
4. Stir through the leeks and sprouts, then transfer to an ovenproof dish and top with the breadcrumbs and the remaining cheese.
5. Heat the oil over a medium-high heat in a frying pan, while you mix the herbs together on a plate. Quickly sear the meat on all sides, then roll in the herbs. Put in a roasting tin and drizzle with a little more oil. Cook the lamb and the gratin in the oven for 15-20 minutes until the lamb is cooked but still pink in the middle, and the gratin is golden and bubbling. Leave the lamb to rest for 5 minutes on a warmed plate, loosely covered in foil, then slice into pieces and serve with the gratin.