1 slice onion, 1/4 inch (5 mm) thick
a few parsley stalks
20驳/戮辞锄 plain flour
1 bay leaf
salt and freshly milled black pepper
1 blade of mace or a pinch of powdered mace (optional)
10 whole black peppercorns
40驳/1陆辞锄 butter
425ml/15fl oz milk