1.Peel onions and cut into eight wedges. Combine vegetables in large baking dish with garlic and seeds; coat with olive oil spray.
2.Bake uncovered, in oven heated to 190°C/375°F, turning occasionally, for about 40 minutes or until vegetables are tender and golden brown.
3.Puree vegetables with stock, in batches, in food processor or blender until smooth; strain into large saucepan. Cover; bring to a boil. Serve topped with coriander leaves.