1 paper-thin, lengthwise slice of a large cucumber, for garnish
1/4 teaspoon finely chopped dill, plus 1 dill sprig, for garnish
1 tablespoon agave syrup
1 tablespoon fresh lemon juice
1 tablespoon fresh lime juice
1/4 cup fresh cucumber juice (see Note)
1/4 cup chilled club soda
Press the cucumber slice against the inside of a chilled highball glass and add ice. In a cocktail shaker, muddle the chopped dill, agave syrup, lemon and lime juices and 1 tablespoon of water until the syrup is dissolved. Add ice, then add the cucumber juice and shake well. Strain into the prepared glass and stir in the club soda. Garnish with the dill sprig.
Note: You can also make it by pureeing peeled cucumber chunks in a blender and then straining the puree through a fine sieve. One large cucumber yields about 3/4 cup strained juice.