Iced Coffee with Vanilla

A two-line recipe that depends almost entirely on the strength of the coffee you start with. Brewed at ordinary drinking strength it will taste thin once cream and melting ice go in.

• Brew it strongMake the coffee at roughly half again the usual strength — the cup of cream plus cracked ice diluting in the glass will flatten anything brewed to normal drinking strength. Cold brew concentrate diluted less than the package suggests works well here.
• "Boiled coffee""Boiled coffee" meant grounds brought up in water in an open pot and settled with a dash of cold water or an eggshell, not a modern drip. Percolated is simply the other method the book's readers were likely to own; a modern drip or cold brew will do, though the flavour will not be identical.
• Chill before you pourCool the coffee fully in the refrigerator rather than pouring it hot over ice. Hot coffee melts the ice instantly and turns the drink watery and dull.
• Cream"Cream" in this period was not standardised and could mean anything from thin table cream to something much richer. Light or table cream (about 18-20% fat) is a reasonable modern stand-in; half-and-half gives a lighter drink and heavy cream a noticeably rich one across six servings.
• VanillaHalf a teaspoon across six cups is subtle by design — it reads as a rounding of the coffee's bitterness rather than as a flavour. Use extract, not imitation, and add it to the cold coffee so nothing evaporates.
• SugarGranulated sugar dissolves slowly and grudgingly in cold coffee. Sweeten while the coffee is still warm, or stir in a simple syrup after chilling.
• Cracked iceIce was commonly chipped or cracked off a block with an ice pick rather than turned out as cubes. Coarsely crushed ice is the equivalent; it chills faster but also dilutes faster, so serve promptly.
• YieldSix cups of coffee plus a cup of cream gives about six tall glasses once ice takes up room in each.