Cooking with hay is an old method, almost like the French en papilotte. The hay keeps the heat in and gives the meat a grassy taste. But it's important to soak the hay before using if it smoulders it will give the delicate lamb a taste you don't want. This method works especially well in Agas where you can lose heat if different things are cooking in the oven and the door is being opened and closed. Ask your butcher to keep the knuckle bone on the lamb when he bones and rolls it as it looks much better and you can hold on to it to carve. You can also use best end or shoulder, which will affect the cooking time. Best end will need only about 25-30 minutes, a shoulder about double that. Pet shops and garden centres sell clean hay.
1 leg of lamb, weighing about 1-1.2kg, boned and rolled
A little vegetable oil
1 head of new-season garlic or a few cloves of normal garlic, thinly sliced
A few sprigs of rosemary or lavender
Salt and freshly ground black pepper
A couple of good handfuls of clean hay, soaked in cold water for 15 minutes and drained
Pre-heat the oven to 220°C/390°F/Gas mark 7. Season the lamb with salt and freshly f ground black pepper, then heat a little vegetable oil until almost smoking in a heavy frying pan large enough to fit the lamb. Seal the lamb on all sides until nicely browned then remove from the pan. Make 9 or 10 incisions about 1cm deep through the skin of the lamb and insert a slice of garlic and a sprig of rosemary in each. If you are using new-season garlic you will only need to peel the outer skin.
Put the lamb into a roasting tray and pack the hay around it. Cover with foil and cook in the oven for 35 minutes. Remove the foil and turn the oven down to 190°C/375°F/Gas mark 5 and cook for another 15 minutes for medium rare.
To serve, leave to rest for 15 minutes, remove the hay and carve. If you leave it in the hay any longer it will continue cooking to medium. Serve with the first of the new-season Jersey Royals roasted in a little olive oil. Feed the hay to pet rabbits or put it round the strawberry plants. Reuse content