Method:
1 Preheat oven to 200°C fan forced.
2 Combine sugar, raspberries and corn flour in a blender, blend until smooth. Transfer mixture to a bowl and stir in the egg yolk.
2 Using an electric mixer, whisk the egg whites until soft peaks, slowly add the extra sugar whisking constantly until sugar dissolves.
3 Add 1/3 of the egg white mixture to the berry mixture and stir in, then carefully fold in the remaining egg white mixture.
4 Grease the soufflé ramekins with butter and dust with caster sugar, spoon mixture into the moulds so they are full. Place on an oven tray. Bake for 15 minutes or until well risen and light golden on top.
5 For the chocolate sauce, place the cream in a saucepan and bring to the boil, reduce heat to low, add the chocolate and whisk until melted, add the butter and continue to whisk until well combined.
6 Place soufflés on serving plates, pour over the chocolate sauce. Serve