Bring a large saucepan of water to the boil, then add 1 large cauliflower, broken into pieces, and cook for 5 mins

Drain the cauliflower, then tip into an ovenproof dish. Heat oven to 220C/200C/Gas 7.

Put the saucepan back on the heat and add 500ml milk, 4 tbsp flour and 50g butter.

Keep whisking fast as the butter melts and the mixture comes to the boil – the flour will disappear and the sauce will begin to thicken. Whisk for 2 mins while the sauce bubbles and becomes nice and thick.

Turn the heat down, stir in most of the grated cheese and pour over the cauliflower once fully melted. Scatter over the remaining cheese.

Put in the oven for ~20 minutes until bubbling and slightly brown in some areas on top