Parsley sauce

• 150 ml (¼ pint) chicken stock
• 275 ml (½

Heat the chicken stock and the milk together with the chopped celery and sliced onion, over a very gentle heat, until it reaches simmering point.

While the liquid is absorbing the flavours of celery and onion, pick over the parsley, removing the thick stalks. Wash it well and dry it before chopping it finely. Now strain the liquid through a sieve. Make a white roux by heating the butter