250g white chocolate, broken into pieces
1 teaspoon vanilla extract
¼ cup (55g) caster sugar
300ml thickened cream
2 x 150g boxes Lindt Lindor White chocolate balls
Melt chocolate in a heatproof bowl over a pan of simmering water (don't let the bowl touch the water). Remove from the heat, then stir until smooth. Set aside to cool.
Meanwhile, separate 2 eggs and set the eggwhites aside. Place the 2 egg yolks, remaining whole egg, vanilla extract and 2 tablespoons sugar in the bowl of an electric mixer and beat until thick and pale.
Lightly whip the thickened cream to soft peaks. Fold melted chocolate and cream into egg mixture until combined.
In a separate bowl with clean beaters, beat eggwhites with remaining 1 tablespoon caster sugar until soft peaks form. Fold into egg mixture to just combine, keeping as much air in the mixture as possible. Place mousse in a glass serving dish and cover with a layer of Lindor balls. Chill for 4-6 hours until mousse is set, then serve.