Cut the cauliflower into florets and cook in boiling water for 5 minutes, then drain in a colander and refresh under cold running water, then allow to drain.
In a pot lightly cook the flour in 2 tbls of the butter.
Add the milk and cook, beating with a wooden spoon or whisk.
Take off the heat, add the cheese and season with salt and pepper.
Put the white bread and the remaining butter into a food processor and blend until it’s a coarse crumb.
Place the cauliflower florets into a wide baking dish, cover with the cheese sauce and scatter the bread crumbs over.
Bake at 180°C for 15-20 minutes and serve.