Roast lamb with onion gravy

Method

Preheat oven to 200ºC (180ºC fan, gas mark 6). Weigh the lamb to calculate the cooking time. Allow 20min per 450g (1lb), plus an extra 20min for medium to well-done meat.

Make incisions in the lamb and insert the garlic pieces. Rub the lamb with salt and pepper, place in a baking dish and scatter around the onions and rosemary. Pour in the wine and 250ml (9fl oz) cold water, and cover the dish with foil. Roast in the oven, basting once or twice and removing the foil for the last 30min.

Transfer the lamb to a carving board, cover with foil and leave to rest in a warm place for 15-20min.

Meanwhile, make the gravy. Drain any liquid from the baking dish into a jug. Discard the rosemary. Melt the butter with the onions in a saucepan, add the flour and cook, stirring, for a couple of minutes. Add the stock and reserved cooking liquid and simmer for 10min, stirring, until sauce thickens. Stir in the crème fraîche, taste for seasoning, pour into a warmed jug and serve with the lamb.