Herb-scented lamb with balsamic dressing
Preheat the oven to 200°C/400°F/Gas mark 6.
Put 2 or 3 sprigs of the thyme and rosemary on a board, put one lamb fillet over them, season with pepper, then top with a further 2 or 3 herb sprigs. Tie the herbs and lamb into a bundle with string, secured at about 5cm/2in intervals. Repeat the process with the remaining lamb and herbs.
Put the lamb in a roasting tin with the garlic cloves, and drizzle with 4 tablespoons of the oil. Roast in the oven for 25–30 minutes.
Remove the lamb from the roasting tin, and put to one side in a warm place, covered with foil. Put the pan juices and garlic cloves into a bowl to one side. Heat the remaining oil in the roasting tin, then add the reserved garlic cloves, the spring onions and the tomatoes. Sauté gently for 5 minutes, lift out and put to one side. Pour the vinegar into the tin, and bubble to reduce by half. Add the stock and reserved pan juices, bring to the boil and bubble for 5–10 minutes. Add the chopped thyme and return the garlic, spring onions and tomatoes to the tin.
Remove the string from the meat, and cut the lamb into thick slices. Serve with the hot dressing spooned over.