To extract the best flavour from a fresh bay leaf, firmly fold it in half or scrunch it in your hand to break the spine before adding it to the bowl. This releases the essential oils.
Combine the milk, onion, cloves, bay leaf, peppercorns and mace in a medium-sized microwaveable bowl. Place in the microwave and cook for 2 mins on High. Remove, cover with cling film and stand for 15 mins, or chill for up to 2 days if the milk’s sell-by date allows.
When you’re ready to serve, strain the sauce, then return to the bowl. Add the breadcrumbs, place in the microwave again and cook for 3 mins on High. If the sauce is a bit lumpy, whisk until smooth, then stir in the cream, nutmeg and seasoning. Finish with a knob of butter.