Make the simple syrup by heating equal parts honey and water in either the microwave or on the stove. Heat until the honey is dissolved, then transfer to a heat-safe container and allow it to cool.

Add the lemon juice, honey simple syrup, and fresh rosemary to a cocktail shaker. Muddle. Add in gin or vodka, add in the ice, and shake. Strain into two glasses filled with ice. Top with Klarbrunn Pomelo Grapefruit Sparkling Water.

Garnish with lemon wedges or rosemary sprigs.