Place the parmesan cheese into the TM bowl and grate on Speed 10 for 10 seconds. Set aside.
Place the chopped cauliflower and vegetable stock into the TM bowl. Season with salt and pepper. Cook for 25 minutes, 100 degrees, Speed 1.
Meanwhile, cook the bacon until crispy in a frying pan on the stove-top, or alternatively, place the bacon pieces onto a baking tray and cook in an oven preheated to 190 degrees celsius (about 15-20 minutes).
Add the butter to the Thermomix bowl and puree on Speed 8 (slowly increasing) for 2 minutes or until completely smooth and creamy.
Add half of the parmesan cheese and mix for a further 30 seconds on Speed 8.
Optional: serve the soup with the crispy bacon pieces and the remaining parmesan cheese.