A champagne cocktail is an alcoholic cocktail made with sugar, Angostura bitters, champagne, brandy, and a maraschino cherry as a garnish.
Other variations include grenadine, orange bitters, cognac (substitute of brandy) or sparkling wine (substitute for champagne).
Other possible garnishes include strawberries or dried orange slices.
A recipe for the cocktail appears as early as "Professor" Jerry Thomas' Bon Vivant's Companion (1862), which omits the brandy or cognac and is considered to be the "classic" American version.
[1] Harry Johnson was one of the bartenders who revived the model by adding other fruit to the mix.