Cut two fresh limes in half and juice them using a citrus juicer to extract about 1/4 cup (60 ml) of fresh lime juice.

Fill two tall glasses with ice cubes, packing them loosely so the soda can flow around them.

Pour 1.5 tablespoons (22.5 ml) of simple syrup into each glass over the ice.

Divide the lime juice evenly, pouring approximately 2 tablespoons (30 ml) into each glass.

Slowly pour 1/2 cup (120 ml) of cold sparkling water into each glass to maintain carbonation.

Stir gently with a long spoon for 10 to 15 seconds until the syrup is fully integrated.

Taste the soda and adjust by adding more lime juice for extra tartness or more sparkling water for milder sweetness.

Garnish each glass with a fresh lime wheel and serve immediately while the soda is fizzy.