Using a channel knife or vegetable peeler, cut a single continuous spiral of peel from one whole lemon, keeping as much white pith off as possible.
Fill a highball glass with ice cubes.
Drape the lemon peel spiral inside the glass so one end hooks over the rim and the rest coils down to the bottom.
Pour 40ml of cognac over the ice.
Top with 100ml of ginger beer, pouring slowly down the side of the glass to preserve carbonation.
Add 2–3 dashes of Angostura bitters directly onto the surface of the drink.
Serve immediately without stirring.
The defining feature of a Horse's Neck is the unbroken lemon peel spiral - take your time cutting it from tip to tip in one continuous ribbon, as the presentation is as much a part of the drink as the taste. Traditionally made with bourbon in the US, the cognac version is the more refined European interpretation and the one most bartenders consider canonical.
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