Pour the cream into a saucepan and bring gently to a simmer, stirring occasionally. Add the sugar and stir until dissolved
Add the lemon juice and bring to the boil, tasting to check the sweetness - you may wish to add a little more lemon juice or sugar as necessary
Simmer for 2 minutes before removing from the heat. Whisk well and then pour the posset into two heatproof glasses
Leave to cool then chill in the fridge for about 3 hours until set before serving. Top with a few berries if you like