Chill a cocktail glass in the freezer or with ice water.
Add 30ml white rum, 30ml cognac, 30ml triple sec, and 20ml freshly squeezed lemon juice into a cocktail shaker.
Fill the shaker with ice and shake vigorously for 10–12 seconds until well chilled.
Discard the ice from the chilled glass.
Double-strain into the chilled cocktail glass.
Garnish with a lemon twist.
Between the Sheets is closely related to the Sidecar - swap the rum for an extra measure of cognac and you're nearly there. The rum softens the brandy's richness and keeps the drink from tipping too sweet, making ingredient quality, especially a good VS or VSOP cognac, essential.
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