To make the base, place the cornflour in a mixing bowl and gradually stir in the wine.
Transfer the mixture to a saucepan and bring to the boil, stirring continuously. Boil for one minute then remove the pan from the heat.
Place the sugar in a clean small pan with a splash of water and boil until it reaches 121C/250F or until it becomes syrupy, taking care not to burn the sugar.
Pour the syrup over the cornflour and wine mixture, allow to cool before transfering to a food processor or blender and blend until smooth then chill until ready to use.
For the soufflé, preheat the oven to 175C/350F/Gas3½. Butter four ramekins, each 7.5cm/3in wide and 4cm/11/2in high, and dust the insides with caster sugar.
Whisk the egg whites until they hold soft peaks, then gradually add the sugar and continue whisking until the mixture is glossy.
Place the cold base in a mixing bowl and whisk in half the egg white mixture. Fold in the remaining egg white mixture, ensuring everything is thoroughly amalgamated.
Fill the ramekins with the soufflé mix and bake for eight minutes.
For the mixed berry salad, mix the berries with the sugar and mint leaves and set aside to macerate for a couple of minutes.
To serve, spoon the berry salad into four small dishes, and top with a spoonful of crème fraiche and a few leaves of basil cress. Place each dish on a plate and place the soufflés alongside. Serve immediately.