In a large soup pan, saute onions, over medium heat until translucent.

Add in cauliflower and cook for few minutes add the garlic, salt, coriander and pepper.

Pour in water or stock and bring to a boil.

Reduce the heat to low and simmer with the lid until cauliflower is tender.

Check for seasoning and adjust accordingly.

Remove from heat and puree until smooth with a hand blender or a food processor.

Serve with yogurt and top with chopped spinach and drizzle with olive oil.