Juice the lemons.
Place the 300 ml of water and the 300g caster sugar in a large saucepan and bring to the boil. When the mixture begins to boil, remove the pan from the heat and allow to cool slightly. When the syrup has cooled down, add the lemon juice and mix well. Stir in the remaining 900ml of water and a few sprigs of mint. Cool the lemonade in the fridge.
When the lemonade is ice cold remove the mint leaves and serve in tall glasses with plenty of ice.
«To make the lemonade fizzy add soda water or sparkling water to the lemon flavoured syrup.»