Whisk together the lemon juice, Simple Syrup and vanilla bean paste in a large pitcher. If not serving immediately, refrigerate the pitcher.
To serve, add the sparkling water to the pitcher and stir to combine. Pour the lemonade into individual glasses of crushed ice. Garnish with a sprig of fresh basil or mint and a lemon slice.
In a small saucepan bring the sugar and water to a boil over medium heat, stirring until the sugar is dissolved. Remove from the heat and cool.