Method:
1 Preheat oven to 220˚C fan-forced
2 Grease two ramekins with extra melted butter, then sprinkle with caster sugar to coat, shaking out excess. Place on an oven tray.
3 Melt butter in a saucepan over medium-low heat. Add flour and stir for 1 minute or until mixture is smooth and begins to bubble. Gradually add milk, stirring until smooth and combined. Return to medium heat, stir until mixture thickens and comes to the boil. Remove from heat. Stir in chocolate, brown sugar and vanilla bean paste until combined. Transfer to a bowl. Add egg yolks and stir until well combined.
4 Whisk egg whites with an electric mixer until firm peaks form. Fold egg whites into chocolate mixture until just combined.
5 Spoon mixture into prepared dishes and smooth tops. Bake in oven for 10-12 minutes or until risen.
6 Dust with icing sugar to serve.