01 - In a small pitcher or large bowl, mix the granulated sugar with freshly squeezed lemon juice until the sugar is completely dissolved.
02 - Stir in the cold water thoroughly. Taste the mixture and adjust the sweetness or tartness by adding additional sugar or lemon juice as preferred.
03 - Fill glasses with ice cubes to chill the drink before serving.
04 - Pour the lemonade into the prepared glasses and garnish each with lemon slices and fresh mint leaves if desired. Serve immediately.