Method

• 1.
  Using a pastry brush, grease 4 x 10cm (300ml-capacity) ramekins or soufflé moulds with butter, using strong upwards strokes. Chill to set these vertical butter tramlines, then repeat with another layer of butter. Dust the inside of the ramekins with extra caster sugar, tapping out any excess. Set aside.
• 2.
  Preheat oven to 200°C with a baking tray inside.
• 3.
  Place milk and 45g caster sugar in a large saucepan over medium heat and bring to the boil. Place egg yolks and 25g caster sugar in a medium heatproof bowl. Using an electric hand beater, whisk until ribbons form, then whisk in the flour. With the beaters running, pour the hot milk in a steady stream over the egg yolks. Return egg yolk mixture to the pan and place back over medium heat for a minute, whisking continuously. Remove from heat and gently stir in the cocoa and chocolate, then cover directly with plastic wrap and set aside to cool.
• 4.
  Place egg whites in the bowl of a stand mixer fitted with the whisk attachment. Whisk to a thick foam, then add remaining 30g caster sugar and continue to whisk to soft peaks.
• 5.
  Remove plastic wrap from the chocolate mixture. Fold in one third of the egg whites to loosen, then gently fold in the remaining egg white. The mixture will be fairly loose.
• 6.
  Divide mixture among prepared soufflé moulds, filling them three-quarters full. Run the blade of a small knife round the top edge of your soufflé to help create an even rise. Carefully place soufflés on the preheated baking tray and bake for 14-16 minutes until risen. Serve immediately with a dollop of ice cream.