Remove the leaves from the cauliflower, and cut the head into florets. Spread them out on a baking tray, drizzle with oil, and roast at 190°C (Gas Mark 5 / 375°F) for around 15-20 minutes, until fairly soft and lightly charred.

Place the roasted cauliflower in a food processor with the beans, cream, garlic and herbs. Blitz thoroughly.

Transfer the mixture to a saucepan, and add the milk, butter and plenty of salt and pepper. Cook over a medium heat, stirring regularly, for 5-10 minutes, until piping hot. You can add additional butter, cream etc. if you feel it needs it.