There’s a gin fizz and then there’s the Ramos gin fizz, a famous cocktail of the Big Easy.
The early “gin fiz” (only one “z,” according to the 1887 edition of Jerry Thomas’s “Bartenders Guide”) called for one teaspoon powdered white sugar, three dashes lemon juice, one wine glass of Holland gin (genever), and a small piece of ice, shaken and served in a medium bar glass and topped with seltzer or sparkling mineral water for the fizzy part.