Cornell Shake

A soda-fountain formula written for someone standing at a counter with syrup pumps and a carbonator. Everything in it translates to a home kitchen, but the proportions assume fountain-strength syrups and a tall glass.

• Vanilla syrupFountain vanilla syrup was a heavy sugar syrup flavoured with vanilla, generally sweeter and thicker than the vanilla syrups sold for coffee today. Something in the region of two parts sugar to one part water, simmered until clear and flavoured to taste, is a reasonable equivalent.
• Plain syrupThe soaking medium is simple syrup with no flavouring, used at the fountain to macerate fruit and keep it from browning. Equal weights sugar and water is the usual modern reading, though fountain guides of the period often ran it heavier.
• Sweet creamThis means fresh unsoured cream, as distinct from soured cream. Heavy or whipping cream gives the body the drink is after; half-and-half will thin it noticeably.
• The fruitThe recipe leaves it open to any finely cut fruit; strawberries, peaches, pineapple and cherries are the sorts of fruit a fountain would have had to hand. Cut them small enough to travel up a straw, and give them the full several hours in syrup so they release juice and colour into it.
• Soda waterUse the coldest, most strongly carbonated water available, and pour it against the side of a tall glass to keep the fizz. The recipe specifies no glass size.
• Assembly and the nameThe recipe gives no mixing instruction despite the word 'shake'; the simplest reading is that syrup, cream and fruit go into the bottom of the glass and the soda does most of the mixing as it goes in. Stir once, briefly, or the carbonation collapses.
• YieldOne glass. The recipe scales directly, but mix each drink in its own glass rather than batching, since the cream and soda separate on standing.