Easy Chocolate Souffle

Ingredients (serves 6)
7 oz good-quality dark chocolate, chopped
3.5 oz butter, chopped
2/3 cup dark brown sugar
5 eggs, at room temperature, separated
2 tablespoons plain flour
2 tablespoons cocoa powder
1/4 cup caster sugar
thickened cream and icing sugar mixture, to serve

Directions:
Preheat oven to 350 F. Grease a 2 inch deep, 8 inch (base) 8-cup capacity square ovenproof dish. Combine chocolate and butter in a heatproof, microwave-safe bowl. Microwave, uncovered, on MEDIUM-HIGH (70%) for 2 minutes, stirring every minute with a metal spoon, until almost melted. Stir until smooth. Stir in brown sugar. Set aside for 10 minutes to cool.
Beat egg yolks with a fork to combine.Stir into chocolate mixture. Sift flour and cocoa together over chocolate mixture. Stir to combine. Using an electric mixer, beat eggwhites until soft peaks form. Add caster sugar, 1 tablespoon at a time, beating until thick and glossy.
Add 1 tablespoon eggwhite to chocolate mixture. Mix well. Using a large metal spoon, gently fold in remaining eggwhite. Spoon mixture into prepared dish. Bake for 35 minutes or until just firm to touch. Dust with icing sugar. Serve warm with cream.