Separate the cauliflower into small florets and blanch until just tender in boiling salted water. Leave to cool. In a small pan, gently heat the milk.
In a separate medium pan, melt butter, then stir in the flour to create a paste or roux. Cook the roux gently for 4-5 minutes, then add the warm milk stirring continuously. Keep cooking the sauce for 4-5 minutes or until it has thickened to a consistency that coats the back of a spoon.
Remove from the heat and stir in the cheese, salt and pepper, mustard, Tabasco and Worcestershire sauce. Layer the florets and sauce in an ovenproof bowl and top with grated cheese. Bake in the oven at 190C/Gas Mark 5 for about 30 minutes until golden brown on the top.