Preheat oven to 180 C. Place carrots (trimmed and peeled), potatoes (halved or quartered), and onions (wedges) on the tray and spray with olive oil. Bake veggies for 20 minutes. Add the sprouts to the tray; spray with a little more oil. Bake for a further 25 - 30 minutes, or until veggies are golden and tender