Parisian Cream

The book prints only the proportions, in the terse style of a period cook's memorandum: this is a boiled-sugar icing of the type poured onto a beaten egg white, tinted and flavoured with burnt sugar. What follows is what the list assumes the cook already knows.

• The hinge: syrup temperatureThe book gives no stage, but a boiled icing of this type depends on cooking the 2 cups sugar and 3/4 cup water to about the soft-ball stage (roughly 238-240F) before it goes onto the stiffly beaten white. Much under that and the icing is slow to set; much over and it turns grainy and hard before it can be spread.
• Burnt sugarNot brown sugar and not molasses. Burnt sugar was a kitchen staple made by melting granulated sugar in a dry pan until deep mahogany, then carefully thinning it with a little boiling water and bottling it. It served as both colouring and flavour; the nearest modern equivalents are a dark caramel syrup or a good caramel extract.
• Egg white and food safetyEgg white and technique -- The white is not cooked separately; the near-boiling syrup, poured in a thin stream while beating, partly cooks it, though this does not reliably pasteurise the egg. Pour slowly and steadily down the side of the bowl rather than dumping it in, or you will get sweet scrambled egg.
• No method printedThe original gives none, so the sequence is inferred from standard practice of the period: beat the white to firm peaks, boil the syrup, pour and beat until the mixture thickens and loses its gloss, then add the burnt sugar.
• Beating by hand versus machineThis kind of icing was beaten with a wire whisk or rotary egg beater for several minutes after the syrup went in. A stand mixer on medium-high does it in three or four minutes and gives a more reliable result, since the mixture must cool while still in motion.
• HumidityBoiled icings are sensitive to damp air and will stay tacky on a humid day. Cook the syrup a couple of degrees higher rather than a couple lower if the kitchen is muggy.
• YieldOne white with two cups of sugar should make roughly enough to fill and cover a two-layer 8- or 9-inch cake. Spread it while still warm and workable; it crusts quickly.