Start as for a béchamel, melting 1-1/2 oz. butter in a heavy saucepan; as soon as it begins to foam stir in, off the fire, 2 tablespoons of sifted flour. forming.

When the mixture is smooth and palest yellow, start adding the hot clear broth.

Return to a low fire and stir patiently until your sauce is thick and smooth. Now add cream and continue stirring. At this stage, the sauce looks much too thin but gradually, as you stir, it thickens. It will take about 20 minutes, over the lowest possible heat, before it is the right consistency. It need not be stirred continuously, only every now and again, in order to prevent a skin

Two or three minutes before serving, stir in egg yolks well beaten with a little lemon juice. This addition greatly improves the sauce and gives it a final smoothness and finish. It may just be allowed to bubble once without risk of curdling, but not more. A little very finely chopped parsley and tarragon is a great improvement to the flavour.

This sauce may be poured over carved chicken before serving, without fear of its developing the pasty looking, and tasting, quality of an ordinary white sauce.