Cauliflower mac-n-cheese

I got the recipe for this out of Sunday's newspaper.  It combined two things I like, cheese and cauliflower, and in a unique but insanely obvious way - through the medium of mac -n-cheese!  I've had cauliflower smothered in cheese in England, and my friend Pete had said that it is a regular dish over there - in fact he was aghast that me and my sister had never had it at home!  We had it and LOVED it! 
Here is my take on the dish - it involves swiss cheese, white sharp cheddar cheese, and ricotta cheese.