Peel and quarter the onions.
- 1 Place the milk, onion, peppercorns and herbs into a saucepan, and bring to a boil.
- 2 Reduce the heat to very low, and leave to simmer gently for 15 minutes.
- 3 Remove from heat and strain, then return the strained liquid to the saucepan.
- 4 Discard the onion, etc.
- 5 Add the breadcrumbs and simmer for a further 5 minutes or so, stirring occasionally, until the breadcrumbs have absorbed the liquid and your sauce has the desired consistency.
- 6 Stir in the butter, and season with salt and pepper to taste.
- 7 Serve warm, sprinkled with nutmeg.