Instructions

1. Finely chop the shallots, garlic, and ginger (and turmeric root, if used). Roughly chop the carrots.
2. Heat the oil in a saucepan and gently sauté the onion for 5 minutes. Add the garlic, ginger and turmeric root and carrots. Cook for 3 minutes, then add the spices and tomato purée. Stir for a minute or so, then add the stock and bring to the boil.
3. Turn down the heat and gently simmer for 15-20 minutes, until the carrots are tender. Add the watercress, cover and turn off the heat.
4. Rest for 2 minutes, then whiz it into smooth, silky soup, using a stick blender.
5. Serve warm.