Place the rhubarb, caster sugar and vanilla pod into a small heavy-based pan over a low heat.
Cook gently for 8-10 minutes, until the rhubarb is tender but still holding its shape.
Transfer the rhubarb mixture to a bowl and leave to cool. Discard the vanilla pod.
Meanwhile, whip the cream until soft peaks form when the whisk is removed, then carefully fold in the crushed meringue nest.
To serve, spoon the cold rhubarb into a tall serving glass and top with the cream and meringue mixture. Dust with icing sugar and serve.