Delmonico Ice Cream with Angel Food

A rich French-style frozen custard: seven yolks to two cups of milk, lightened with whipped cream rather than plain cream. Most of the work is in the custard, and the one thing that ruins it is heat.

• Cook the custard gentlyStir the milk, sugar, yolks and salt over low heat or in a double boiler until it coats a spoon, around 170-175F; much above 180F and the yolks begin to curdle. The recipe's instruction to strain catches any bits that do set.
• "Thin cream" and the whipThin cream in this period was roughly 18-20 percent fat, unhomogenised, and was routinely whipped, though it would not hold as heavy cream does. Supermarket light cream will not whip; use heavy cream if you want the airy result the method intends, or simply fold in whipped cream in the same volume.
• "Remove whip"The instruction means to skim off the risen foam with a skimmer as it forms, returning the unwhipped cream underneath to the bowl to beat again. What the two quarts measures is not clear: 2 1/2 cups of cream will not yield two quarts of foam, so the figure may cover the custard and whip combined.
• One tablespoon vanillaNot a misprint. A full tablespoon is right for roughly two quarts of base, and freezing dulls flavour, so under-flavouring shows badly.
• "1 teaspoon lemon"The original does not say whether this is lemon extract or juice. Extract is the likelier reading for an ice cream of this type; a teaspoon of juice would be negligible.
• FreezingWritten for a hand-cranked churn packed with ice and rock salt. In a modern machine, chill the base thoroughly overnight first, then churn; the whipped cream already carries air, so it will finish quickly.
• YieldSomewhere between two and three quarts once frozen. Ripen it in the freezer for a few hours before serving.
• Angel FoodThe accompaniment is angel cake, sliced and served alongside. Any plain white sponge does the same job.