grate the cauliflower with a grater or food processor to rice size.
Add ⅓ of the butter to a big frying pan on medium heat. Add the chopped mushrooms and garlic and fry until they're soft and golden brown. Season with salt and white pepper.
Lower the heat, add the cauliflower and the rest of the butter. Let the butter melt.
Pour in the white wine and stir a bit until the wine has evaporated.
Add some of the vegetable or chicken stock, stir often until the stock has evaporated. Once it has evaporated, add more stock and repeat until you've used most of the stock.
Once the cauliflower has softened, add the heavy cream and the rest of the stock.
Let it simmer until it has the consistency you're looking for. Add more stock/heavy cream if needed.
Add the parmesan and stir until it is incorporated into the risotto.
Serve and enjoy!