Fry the onion in the olive oil and butter until it starts to become translucent.
Add the root vegetables and fry for about a minute
Throw in the cauliflower and stir until coated.
Pour in the stock (if it's not enough to cover, top up with water)
Season with salt and pepper
Bring the pot to the boil and then drop the head to a simmer and cover.
Cook until the cauliflower is very soft
Blitz the soup with either a stick blender or in a regular blender.
Return to the heat and simmer to thicken.
Taste to see if more seasoning is needed.
in the meantime put the sliced garlic in a pan with the oil and fry until slightly browned.
To serve, pour the soup into the bowl and then pop a few pieces of garlic in, sprinkle the oil to make a pretty pattern.