Add the sliced red chili pepper to the cocktail shaker and muddle gently to release the heat without pulverizing the flesh.
Add the vanilla vodka, elderflower liqueur, fresh lime juice, and honey syrup to the shaker.
Fill the shaker with ice and shake vigorously for 12–15 seconds until well chilled.
Double-strain through a fine mesh strainer into a chilled cocktail glass to remove chili seeds and ice shards.
Garnish with a whole red chili pepper on the rim or resting across the glass.
Muddling the chili briefly rather than aggressively is key - you want infused heat, not a bitter, vegetal mess. Taste the chili before using; heat levels vary enormously between individual peppers.
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