Clean the cauliflower from outer leaves and trim off its hard bottom.
With a small knife separate the white inside cauliflower part into large florets and wash in cold water. Put them into a pan and cover with milk. Add a pinch of salt and cook on a small heat until the florets start to turn a little bit soft.
In the meantime heat the cream in a separate pot. Drain well the cauliflower florets (once they are ready) and add them to the pan with the cream. Simmer for further 5 minutes (the cauliflower should be soft by now, if not allow more time to cook) and transfer the mixture into a food processor and blend until you obtain a smooth purée.
Season the cauliflower purée with salt, some nutmeg and freshly ground pepper.