Cook the quinoa according to pack instructions. Meanwhile, heat 3 tbsp of the oil in a wok or large pan, then add the garlic and quickly fry for 1 min. Throw in the carrots, leeks and broccoli, then stir-fry for 2 mins until everything is glistening.
Add the sundried tomatoes, mix together the stock and tomato souce, then add to the pan. Cover, then cook for 3 mins. Drain the quinoa, then toss in the remaining oil and the lemon juice. Divide between warm plates and spoon the vegetables on top.