Start by making a saute with olive oil, onion and garlic, in medium heat.
Add 10 mushrooms and the coriander and cook for a few minutes.
Add the potato and cook for another 3 or 4 minutes.
Add the cauliflower florets and cook again for another 3 or 4 min.
Add the broth, the milk and the salt and let it boil.
Add the water and let it boil.
When the vegetables are very soft, turn off the heat.
Blend the mixture in a food processor, blender or even with a hand blender.
Add nutmeg and blend again.
Saute the remaining 4 mushrooms with olive oil and a dash of soy sauce.
Sprinkle the soup with fried onions.