Combine Old Tom Gin, Maraschino liqueur, fresh lemon juice, and orange bitters in a cocktail shaker.
Add ice and shake vigorously for 10–12 seconds until well chilled.
Double-strain into a chilled coupe glass.
Garnish with a expressed lemon zest twist and a Maraschino cherry.
The Casino is a close relative of the Last Word family and dates to Hugo Ensslin's 1916 'Recipes for Mixed Drinks.' Old Tom Gin is essential here - its residual sweetness balances the lemon without needing added sugar, so do not substitute London Dry.
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