01 - Combine the granulated sugar and 1 cup of warm water in a small pitcher. Stir until the sugar is fully dissolved.
02 - Add the freshly squeezed lemon juice and the remaining 3 cups of cold water to the dissolved sugar mixture. Stir thoroughly to blend.
03 - Taste the lemonade and modify sweetness or tartness by adding more sugar or lemon juice as preferred.
04 - Refrigerate the lemonade for at least 30 minutes or serve immediately over ice cubes.
05 - Optionally garnish with lemon slices and fresh mint leaves before serving.