Muddle the kiwi pieces and mint leaves in a cocktail shaker until the fruit releases its juice.
Add vodka, lime juice, and simple syrup to the shaker.
Fill the shaker with ice and shake vigorously for 15-20 seconds.
Strain the mixture into a highball glass filled with fresh ice.
Top with club soda and stir gently.
Garnish with a kiwi slice and mint sprig.
Notes
The drink tastes best when using ripe kiwis. Green kiwis work better than gold kiwis for this recipe.Keep the mint leaves whole when muddling to avoid bitter bits in the drink.Make it non-alcoholic by replacing vodka with sparkling water.Store simple syrup in the fridge for up to 2 weeks.Double-strain the mixture if you want to remove kiwi seeds from the drink.