Rim a rocks glass with caramel syrup or sugar, if desired.
Fill a cocktail shaker halfway with crushed ice.
Add vodka, apple cider, caramel syrup, and lemon juice to the shaker.
Shake for about 15 seconds until well-chilled.
Strain into the prepared glass filled with fresh ice.
Top with club soda and stir gently to combine.
Garnish with apple slices and a light caramel drizzle; sprinkle a pinch of cinnamon if you like.
Notes
Caramel vodka amps up the flavor, but plain vodka works too. For a less sweet drink, reduce the caramel syrup slightly.Make it a mocktail by skipping the vodka and adding more cider or sparkling water. Serve immediately to keep the bubbles lively.