Complex sentence: Elderflower heads are steeped in a concentrated sugar solution so the flavour of Elderflower is extracted into the sugar solution, the flowers are then removed and lemon juice is added to help preserve the cordial and add a tart flavour.
Split into simpler sentences: Elderflower heads are steeped in a concentrated sugar solution so the flavour is extracted into the sugar solution. The flowers are then removed and lemon juice is added to help preserve the cordial and add a tart flavour.