I parboil the cauliflower in florets, drain and place in an ovenproof dish. Then make a basic roux (melt butter, add plain flour, cook off for a couple of mins, gradually add milk. Whe sauce thick enough, turn off heat and add grated cheese to taste. A dash of mustard with the sauce is nice. Pour over cauli and either grill or place in oven. Nice with breadcrumbs and grated cheese on top). Enjoy!