Heat the milk with the vanilla pod until just below boiling. Remove from heat, cover and infuse for 10 minutes.

Whisk egg yolks with 70 g sugar until pale, then whisk in cornstarch. Remove vanilla pod, reheat milk and slowly pour it into the egg mixture while whisking.

Return mixture to the saucepan and cook over medium heat, whisking constantly, until thickened. Remove from heat and stir in drained gelatin until dissolved.

Transfer custard to a bowl, cover surface with cling film and cool to room temperature.

Whip the cream to soft peaks and gently fold into the cooled custard to create a light filling.

Heat water, remaining sugar and lemon juice briefly to dissolve sugar, then cool. Lightly dip sponge fingers into the syrup.

Line a charlotte mould or deep bowl with the soaked sponge fingers. Spoon in half the cream, add berries, then top with remaining cream. Cover with more sponge fingers if needed.

Cover and refrigerate for at least 4 hours until fully set. Unmould carefully before serving.