Add light rum, brandy, fresh lemon juice, and raspberry syrup to a cocktail shaker.
Fill the shaker with ice.
Shake vigorously for 10–12 seconds until well chilled.
Double-strain into a chilled cocktail glass.
Serve immediately, ungarnished.
The Quaker's Cocktail appears in early 20th-century bar guides and is a rare example of a split-base shaken sour pairing rum and brandy as equals - neither dominates, making spirit selection critical. Use a clean, light agricole-style rum and a VS Cognac for the most balanced, historically plausible result.
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