Heat a little canola oil in a large pan and cook the onion and garlic with a pinch of salt until just softened.
Cut the cauliflower into small florets an slice the stalks thinly.
Add the cauliflower to the pan along with the thyme. Cover with the water and milk,
Simmer for 20 minutes until the cauliflower is very soft.
For the croutons
While the cauliflower is cooking heat the butter in a skillet. Add thre thyme, garlic and berad cubes. Fry until lightly golden in color and crisp. Grate in the parmesan. Remove from the pan and set aside, keeping warm.
To finish
Add the cheese and mustard to the soup and blend until smooth with a hand blender. Season with a little white wine vinegar, Worcestershire sauce and salt and pepper to taste.
Serve in bowls garnished with the croutons, a sprinkling of fresh thyme leaves and a turn of frsh ground black pepper