When I was thinking this recipe through, I realised that it's such an heirloom that I don't know exact ingredients. I just - well - make it. No measuring, no weighing. So this is what I do.
Take one fine cauli and cut out the thick stem. Break into flourets. Grate your cheese - tonight I used Lord of the Hundreds, a lovely hard sheep's cheese, some gruyere and Keen's chedder - about a third of each.
Add a glass of milk to a pan of simmering water so that the liquid will just cover the flourets. While you're waiting for it to come up to the boil, add a large knob of butter to a seperate saucepan and when the butter's melted, add a hefty spoonful of plain flour. Mix well and keep over the heat for a couple of minutes, stirring all the while. By now the milk/water mix should be on the boil - add the flourets. Turn off the heat under the flour roux, and start adding a ladleful of the boiling cauli liquid to the roux and stir well to combine. Using hot liquid means that the roux will thicken immediately - keep adding liquid until the roux has the consistency of double cream. This takes me about five minutes, by which time I drain the cauli flourets and tip them into a warmed bowl. I add paprika or cayenne to the sauce, plus a few gloops of Worcestershire sauce.
Put the sauce back on the heat and let it simmer for five minutes. Then turn off the heat and tip in the cheese. Another stir to amalgamate. Then pour the sauce over the cauliflower flourets and add a handful of cheese over the top. Bung in an oven, gas mark 6, until the top is golden and bubbling - around 20 mins.
Serve with crusty bread - this evening I heated some sesame encrusted Turkish bread in the oven for a few minutes to eat alongside the cauliflower cheese. Perfect comfort food.