For the ice cubes:
2 cups watermelon pieces (no rind, no seeds)
1 tablespoon honey
1 ounce fresh lime juice
Purée the watermelon, honey and lime juice in a blender until smooth. Pour into a square silicone ice cube tray. Freeze until firm, 3 to 4 hours.
For the simple syrup:
¾ cup sugar
¾ cup water
Combine the sugar and 3/4 cup water in a small saucepan. Bring to a simmer and shut off the heat. Stir until the sugar dissolves. Cool.
4 ounces Cîroc Limited Edition Summer Watermelon Vodka
2 ounces fresh lime juice
12 to 14 fresh mint leaves, torn
Club soda, for topping cocktail
Mix the vodka, lime juice, mint leaves and 2 ounces simple syrup in a pitcher filled with ice and stir until chilled. Put 3-4 watermelon cubes in each of 2 highball glasses and pour the cocktail over, straining the ice in the pitcher. Top with club soda.