Place the cream in a mixing bowl and whip until it forms soft peaks, then gradually pour in the elderflower cordial, whisking until combined.
Freeze in a plastic tub until completely frozen. Scoop into a food processor and blend to remove any ice crystals
Transfer to pretty little dessert glasses or Martini glasses for at least three hours or overnight in the freezer.
To serve, place in the fridge for 15-20 minutes to soften slightly, then serve each glass with a few summer berries and decorate with a dusting of icing sugar.
This could also be made with other fruit cordials. But don’t be tempted to use fruit juice, it is the sugar in the cordial that makes the posset freeze smoothly.