Another great recipe from my mother-in-law.
Steam one head of cauliflower. I usually just put it in an 8x8 pan, add some water, and microwave it until done.
2 T milk
2 T melted butter
2 T flour
(these can be more, just maintain the 1:1 ratio)
Pour sauce over cauliflower. sprinkle lots of shredded cheese. microwave until cheese is melted.