The contrast of lightly whipped cream and the intense damsons works wonderfully.
300ml/10fl oz double cream
500g/1lb damson syrup (make as per the chocolate-cake recipe below)
1tbsp icing sugar
Make sure both the syrup and cream are at room temperature. Whisk the cream to soft peaks – don't over-whip as the final texture won't be nice. Fold in the sugar then, as lightly as possible, fold in the syrup. You are looking for a marbling effect. Put in the fridge until ready to eat. You can, if you like, fold in berries left whole.