Peel all the vegetables, then chop them into even cubes, cutting the beetroot slightly smaller than the sweet potato to ensure they cook evenly. Wrap the chopped red onion in a small foil parcel so it cooks through gently without burning.
Spread the remaining vegetables onto a baking tray lined with baking paper.
Add the olive oil and spices, then mix well using your hands so everything is evenly coated.
Bake in a preheated oven at 200°C for 30 minutes, or until tender and lightly golden. Remove from the oven and allow to cool slightly.
To assemble, add the roasted vegetables to a serving bowl, then top with the pomegranate seeds, parsley, walnuts and dressing. Mix well and serve.