1poundunpeeled Persian cucumbersends trimmed, plus more for garnish
11/2 cupsfresh basil leaves(no stems), plus more sprigs on the stem for garnish
6tablespoonsfreshly squeezed lime juice
Pinchcoarse sea salt
1bar spoonorange flower water(optional)
12dashesANGOSTURA orange bitters
1(750 ml) chilledsparkling water
Make The Cucumber Agua Fresca: Combine the cucumber, basil, water, lime juice, honey and salt in the carafe of a blender. Place the top on the blender carafe, then blend until the mixture is smooth, at least 30 seconds.
Strain the mixture twice through a sieve, pushing on the back of the mixture with a spatula to extract as much juice as possible. Discard the solids and set mixture aside.
Make The Cocktail: In a pitcher, mix the cucumber agua fresca, elderflower liqueur, ANGOSTURA orange bitters and 2 cups of ice.
To serve, fill a Tom Collins glass with 3 to 4 ice cubes, add in ½ cup of the cucumber basil agua fresca cocktail mixture and top with ½ cup of sparkling water. Stir to combine, garnish with a sprig basil leaves and some thinly-sliced cucumber and serve.