Preheat the oven to 180°C (160° fan-forced). Line a large roasting dish with baking paper.
In a small bowl, place 1 tablespoon oil, thyme and garlic. Season and stir to combine.
Spread vegetables onto roasting dish, drizzle with remaining oil, season and toss to coat. Place lamb on top of vegetables and brush with thyme mixture. Cover with foil and roast for 1 hour. Remove foil and cook for a further 30-40 minutes, or until lamb is cooked to your liking and vegetables are tender. Remove lamb from dish and set aside covered in foil for 15 minutes to rest. Pour any pan juices into a small saucepan to add to gravy, if desired.
Slice lamb and serve with onions, potatoes, carrots, peas, sugar snaps, spinach, mint sauce and gravy. Garnish with extra thyme leaves
Use leftover leg of lamb in salads, tacos, or fritters, to name a few. Try adding tossed lamb to a salad of baby rocket, canned lentils or chickpeas, baby beetroots and shredded carrot.
Cut your vegetables a similar size to ensure even cooking.