Dave Arnold and Don Lee, the cocktail masterminds behind Existing Conditions in Greenwich Village, like their Manhattans between 21.2 and 28.4 degrees Fahrenheit. But you can’t get to that specific level of frostiness by stirring liquor with ice: Your cocktail would be far too watery before it dipped anywhere near that temperature. Pre-mixing batches of the bar’s rye-forward Manhattan in bottles and stashing them in a precisely calibrated cooler allows Arnold and Lee to separate chilling from dilution, resulting in a perfect drink every time.Lee notes, “Making a bottled cocktail is great for dinner party planning, too, because it lets you do the work ahead of time.” No more stirring drinks at the last minute or fussing with ice and strainers; when your guests arrive, you can spend time being a good host rather than a frazzled bartender. A swing-top bottle will work perfectly (or use a clean, one-liter, plastic seltzer bottle). Store the prepped drink in your freezer until about an hour before serving, then move it to your fridge for a flawless, effortless pour.