Roll the dough and line a lose bottom tart or deep cake tin with the pastry. Place the tart in the freezer until needed. This will help the pastry to bake to a crisper result.
Place the vanilla pod or vanilla bean paste in a saucepan with the milk and water. bring to the boil for 1 minute or so.
In a bowl, place the eggs, caster sugar and cornflour in a bowl and whisk until the preparation is light and smooth.
Pour half the boiling milk over the egg mixture, without stopping whisking, then return to the saucepan. Like for a bechamel or pastry crème, stir constantly over high heat until the cream thickens and takes on a consistency between crème anglaise and custard.
Remove from the heat and pour into a large bowl. Let cool for a while until just tepid.
Preheat the oven to 170°C.
Pour the vanilla custard mixture over the frozen pastry base and place in the oven.
Bake for 50-60 minutes until the mixture ‘soufflé’ and brown on the top. It might burst from the shell a little depending on the tart shell you are using. It will be fine!
Once cooked, remove from the oven and set aside to cool for at least 2 hours.
Place in the fridge overnight for better texture.
Eat preferably at room temperature on the next day.