Rhubarb gin fizz

PREPARATION:

Chop the rhubarb into small pieces and toss them into a bowl along with the Hermesetas Granulated. Bring to the boil, stirring all the time, then simmer until the rhubarb begins to fall apart. Sieve the boiled rhubarb into a bowl, pressing down until all the liquid has been pressed out of the rhubarb. Taste and add more Hermesetas if you wish. Allow the rhubarb syrup to cool. Fill a shaker with a handful of ice cubes and then pour in the lemon juice along with 4 cl of the rhubarb syrup. Add the gin and egg white. Place the lid on the shaker and shake until condensation begins to appear on the outside of the shaker. Fill two glasses with ice cubes and pour the contents of the shaker over them. Top up with sparkling water.