It's so simply to make this lovely lemonade. Place 180g of the raspberries in a tall jug and add enough water to cover them, blend with a hand whisk.
Zest and juice the lemons and mix with the sugar and puree raspberries also add 1 1/2 litres of boiling water. Make sure it is mixed well together so the sugar isn't at the bottom. Leave it to cool, then pour through a sieve into a large jug and push through with a spoon to extract all the lovely juicy flavours. To serve, place in a glass filled with ice, half way and refill the rest with soda water, adding some whole raspberries as a finishing touch.