The Portland
Mix thoroughly with a spoon three tablespoonfuls chocolate syrup with two tablespoonfuls of vanilla ice cream. Add soda water, using the syphon, and pour into a glass to within an inch of the top. Add chopped walnuts and a spoonful of whipped cream.
A soda-fountain drink assembled in the glass rather than shaken, from the era when the fountain was the respectable alternative to the bar. The whole thing takes under a minute once the syrup and ice cream are to hand.
- Chocolate syrup means fountain syrupA sweetened cocoa syrup of the kind kept at the fountain, rather than a modern squeeze-bottle sundae sauce. If your syrup is very thin, it will dilute more readily into the soda.
- Muddle the syrup and ice cream firstThis is the step that matters. Working the ice cream into the syrup with a spoon before any water goes in gives you a smooth base; if you charge it with soda first, the cold syrup sits at the bottom and the drink separates into sweet sludge and plain fizz.
- Syphon versus bottled sodaA syphon delivers carbonated water under pressure, which is what breaks up the base and raises the foam. Chilled seltzer or club soda from a bottle works, but pour it hard down the centre of the glass to get the same agitation.
- Glass sizeThe original does not specify a glass. Filling to within an inch of the top, as directed, leaves room for the cream and nuts without overflow once the head rises.
- Two tablespoons is not a scoopThe ice cream here is a body-and-richness ingredient, not a float. Two tablespoons is about one ounce; a full scoop would give you something closer to an ice cream soda.
- WalnutsChop them fine and, if they have been in the cupboard a while, toast them briefly and cool them first.
- YieldOne glass. Multiply the syrup and ice cream, but charge each glass separately at the moment of serving, since the foam collapses within a minute or two.
On Uncle Sam's Water Wagon belongs to a small genre of American drink books published in the run-up to national Prohibition, when soda fountains were expanding and drugstore dispensers needed a repertoire that could stand comparison with a bar list. Books of this sort commonly named drinks after cities, hotels and states, which is plausibly how a chocolate soda with walnuts and whipped cream ends up as "The Portland" — the name signals nothing about the ingredients. The soda syphon was standard fountain equipment by this date, and building a drink on a base of syrup worked smooth with a little ice cream is what this recipe itself directs.