Bring a pot of salted water to boil. Add the cauliflower florets and turn the heat down to medium. Cook covered for 15 minutes until cauliflower is soft and tender. When the cauliflower is cooked, remove from heat and drain.
While the cauliflower is cooking, heat butter in a frying pan over medium heat. Saute the garlic for about 2 minutes until soft. Set aside.
In a food processor, add the cooked cauliflower, sautéed garlic and the butter it was cooked in, milk, Parmesan cheese, salt and pepper. Puree until smooth.
Serve hot and sprinkle some chives or rosemary on top.