Modifications
The original Old Fashioned recipe would have showcased the whiskey available in America in the 19th century, either bourbon or rye whiskey. But in some regions, especially Wisconsin, brandy is substituted for whiskey (sometimes called a Brandy Old Fashioned). Eventually the use of other spirits became common, such as a gin recipe becoming popularized in the late 1940s. Another common modification is to add soda water.
Common garnishes for an Old Fashioned include an orange slice or a maraschino cherry, although these modifications came around 1930, some time after the original recipe was invented. While some recipes began making sparse use of the orange zest for flavor, the practice of muddling orange and other fruit gained prevalence as late as the 1990s.
Bartenders often use a dissolved sugar-water premix called simple syrup, which is faster to use than granulated sugar and eliminates the risk of leaving undissolved sugar in the drink, which can spoil a drinker's final sip.
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