4 extra large eggs (at room temperature), separated
1/4 cup (55g) golden caster sugar
400ml thickened cream
Pour boiling water into a large saucepan about a quarter full and sit a large bowl on top, making sure the bottom does not touch the water. Add 180g chocolate, stirring occasionally until chocolate melts. Remove bowl from heat and allow to cool slightly. Place the remaining chocolate in a small bowl and reserve for serving.
Place egg yolks and 2 tablespoons sugar together in a large mixing bowl and using an electric mixer beat until thick and mousse like. Add egg mixture to the cooled melted chocolate, folding gently to combine.
In a large clean mixing bowl, whisk egg whites to soft peaks and add remaining sugar, beating until thick and glossy. Add beaten egg whites to chocolate mixture, folding gently to combine.
Using the same mixing bowl, add cream and beat using an electric mixer until soft peaks form. It is important not to overbeat the cream. Add 3/4 of the whipped cream to the chocolate mixture, folding gently to combine. Place the remaining cream in a small bowl covered in plastic wrap and reserve for serving.
Evenly divide chocolate mixture between six glass tumblers, ramekins or small bowls. Place on a tray in the refrigerator for at least 2 hours to set.
To serve, place a teaspoon of whipped cream on top of each mousse and sprinkle over a little of the reserved chopped chocolate.