Start by making a simple syrup to dissolve the sugar evenly. In a small saucepan, combine 1 cup of water with the sugar and stir over medium heat. Keep mixing until the sugar fully dissolves. Once done, remove it from heat and let it cool completely before adding it to the lemonade mixture. This step prevents grainy sugar crystals in the drink.
In a blender, add the freshly squeezed lemon juice, fresh mint leaves, and the cooled simple syrup. Blend everything until smooth and well combined. The mint leaves will release their essential oils, giving the drink a fresh, cooling taste that pairs perfectly with the tangy lemon.
Once blended, pour the mixture through a fine strainer into a large pitcher. This helps remove pulp and excess mint solids, leaving you with a smooth liquid. Add the remaining 5 cups of cold water and stir well to balance the flavors. At this stage, you can adjust the sweetness by adding a little more syrup if you prefer a sweeter taste.
Fill the pitcher with ice cubes, or add ice directly to serving glasses. Garnish with extra mint leaves and lemon slices for a fresh presentation. Serve immediately while chilled for the most refreshing experience. If you’d like, you can swap 2–3 cups of cold water with sparkling water just before serving for a fizzy version.