Don't miss out on our special Christmas issue with free 2023 calendar - subscribe by 18 October!
Tip the blackberries into a pan with 2 tbsp icing sugar, plus the lemon zest and juice. Simmer until syrupy, then leave to cool. Chill for a few hours.
Whip the double cream with 1 tbsp icing sugar, then swirl through most of the blackberry sauce. Serve in glasses with extra sauce and fresh blackberries on top.