For the mango parfait, place the egg yolks, water and half the sugar into a saucepan and whisk to combine. Place over a low heat and cook gently, stirring occasionally, for about ten minutes, until the mixture thickens.
Remove from the heat and pour into a mixing bowl. Whisk until the mixture cools and is light and fluffy.
Meanwhile, place the mango flesh into a blender and blend until smooth. Pass through a sieve into a bowl.
Add the cream to the mango mixture and whisk until the mixture forms soft peaks when the whisk is removed. Fold in the cooled egg yolk mixture.
Place the egg whites into a bowl and whisk until soft peaks form when the whisk is removed. Gradually add the remaining caster sugar, continuing to whisk until stiff and glossy.
Fold the egg white mixture into the cream mixture until well combined.
Spoon the mixture into six individual pudding moulds lined with cling film. Place into the freezer for 1-2 hours until completely firm.
Preheat the oven to 100C/200F/Gas ¾.
For the meringue stack, place the egg whites into a bowl and whisk until soft peaks form when the whisk is removed.
Gradually add the sugar and continue to whisk until stiff and glossy.
Spoon the mixture into a piping bag fitted with a small plain nozzle. Draw 18 7.5cm/3in diameter circles onto baking parchment and place onto a baking sheet. Pipe the meringue in a spiral to fill each circle.
Transfer to the oven and cook for 20 minutes, then turn the oven off but leave the meringues in there for at least two hours. When crisp, remove from the oven and allow to cool completely.
Remove the parfait from the freezer five minutes before serving.
To serve, place a meringue disc onto each of six serving plates. Spread a little whipped cream over them, then drizzle with the passion fruit flesh. Top with another meringue and the remaining cream and passion fruit, then finish with a third meringue.
Turn the parfaits out onto the plates with the meringues. Dust the meringue stacks with icing sugar and top with a few mango slices.
