Roast leg of lamb with wild garlic dauphinoise

Preheat the oven to 230°C, gas mark 8. Put the lamb in a large roasting tin and rub with the oil; season. Roast for 20 minutes until golden brown, turning over halfway. Meanwhile, thinly slice the potatoes to 2-3mm thick (use a mandolin if you have one).

Remove the lamb from the oven and reduce the temperature to 160°C, gas mark 3. Use a sharp knife to make around 15 incisions all over the leg of lamb. Stuff alternate slits with a slice of garlic or rosemary sprig. return to the oven and roast for 30 minutes.

Meanwhile, mix the cream, milk and wild garlic in a jug; season, then pour into a large, heavy-based pan and bring up to a gentle simmer. Stir in the sliced potatoes, then cook gently over a low heat for 5 minutes; season again if needed. Carefully spoon the mixture into a roughly 24x24cm deep ovenproof dish, making sure everything is spread out evenly. Dot with the cubes of butter, cover tightly with foil and put on a large baking tray; set aside.

Baste the lamb, then return to the oven with the dauphinoise and cook for a further 1 hour, ensuring all surfaces of the meat are thoroughly cooked and browned. If you like the lamb medium and blushing pink, take it out and set aside to rest; if you want it well done, cook for another 20-30 minutes. While the lamb is resting, preheat the grill to high and remove the foil from the potatoes. Grill for 5 minutes, or until bubbling and golden. Carve the lamb and serve with the dauphinoise and spring cabbage.