Method

• 1.
  Stud the onion halves with the cloves. Put in a pan with the milk, bay leaf and black peppercorns. Bring to the boil over medium-high heat. Remove from the heat and stand 20 minutes to infuse. Strain the milk into a jug. Discard solids.
• 2.
  Melt the butter in a non-stick pan, add the flour and cook over medium-low heat, stirring, for 1 minute. Remove from the heat and gradually beat in milk with a wooden spoon. Return pan to the stove and bring to the boil over medium-high heat, stirring continuously. Reduce heat to low and simmer very gently for 10 minutes, stirring every now and then.

• 3.
  Meanwhile, preheat grill to high and warm a large, shallow ovenproof dish.
• 4.
  Bring a large pan of well-salted water to the boil. Cut the cauliflower into large florets, discarding thick cone-shaped core and larger, tougher green leaves. Drop the cauliflower florets and young green leaves into boiling water and cook for about 8 minutes (this includes the time it takes for the water to come back to the boil) until tender. Drain the cauliflower and leave briefly for the steam to die down.
• 5.
  Remove the milk mixture from the heat. Stir in the cream, mustard and 100g of the grated cheddar. Season to taste with salt and freshly ground white pepper. Arrange the cauliflower in the dish and pour the sauce over. Scatter over remaining cheese and grill for 3-4 minutes until golden and bubbling.