*Make simple syrup (it really is simple!) by heating 1 cup water with 1 cup sugar and stirring until sugar dissolves. Remove from heat and let cool before using in your drink.
Juice the lemons and pour the juice into cocktail shaker.
Add vodka, St. Germain, and simple syrup.
Close shaker and shake.
Pour liquid into glasses filled with ice.
Top with desired amount of lemon sparkling water.
Garnish with lemon slice and a flower and enjoy!