01 - In a large pitcher, stir together lemon juice and granulated sugar until the sugar dissolves completely.
02 - Pour in the cold water and stir thoroughly to blend.
03 - Gently bruise the mint leaves to release their aroma and add them to the pitcher.
04 - Fill glasses with ice cubes and pour the lemonade over them.
05 - Decorate each glass with a lemon slice and a few mint leaves before serving immediately.