French style vanilla slice (two layers of puff pastry with pastry cream)

Preheat the oven to 200C, about 400F.

In a medium saucepan off the heat put half a litre of milk and one or two tablespoons of sugar.

Flatten the vanilla bean with a knife, split it lengthwise, scrape out the seeds, and add seeds and pod to the milk.

Stir to dissolve the sugar and bring barely to a boil over medium heat.

Separate the eggs; keep the whites covered in the fridge up to two weeks for meringues.

Whisk the yolks with the sugar one to two minutes until paler ('blanchir').

Sieve in the flour and mix gently, then sieve in the cornflour and incorporate.

Pour in about half the hot milk through the sieve, mix, then the rest; pour everything back into the pan through the sieve, returning the vanilla seeds.

Cook on medium heat, whisking slowly, until thick (about four and a half minutes) and boiling, then whisk one and a half minutes more; turn off the heat.

Pour the pastry cream into a cold tray, press cling wrap onto its surface so it does not crust, and chill in the freezer then the fridge until very cold.

Prick the puff pastry sheets all over with a fork and sprinkle with fine caster sugar.

Cover with a baking tray and weights so it cannot rise, and bake 15 to 20 minutes until golden.

Whisk a little rum (optional) into the cooled pastry cream.

Spread as much pastry cream as wanted over the bottom sheet, place the top sheet on gently without cracking it.

Trim all four edges with a knife for clean sides, then cut into slices of the chosen width.

On a cooling rack, sprinkle the top with a layer of sugar and eat at once; keep unsugared in the fridge if holding.