Peel the onion, cut in half and stud each half with a clove. Pour the milk into a small saucepan and add the studded onion, bay leaves and using a fine grater, grate 1/4 of the nutmeg into the pan. Place over a low heat until the milk is on the verge of boiling. Then switch off the heat and allow to sit for 15 minutes allowing the flavours to infuse.

Using a slotted spoon or tongs remove the onion and bay leaves from the milk and discard. Turn a low heat on under the pan, stir in the breadcrumbs until the sauce is warm and the crumbs have amalgamated with the milk and the sauce has thickened. Season to taste.

Switch off the heat and stir through the double cream. Transfer to a serving jug or bowl. Add a knob of butter to the top.