Recipe: Mille feuille

1 Cooking the puff pastry:
500g (17.75 oz) of 6-turn puff pastry that you will roll out to a thickness of 3 to 4 millimeters and that you will prick either with a fork or a docking tool (pastry utensil for pricking pastries), and that you will place on a 30x40 cm rectangular baking sheet.
let rest about 15 minutes and cook for about 15 minutes at 200°C (390°F) at the start for 6 minutes then reduce the temperature to 160°C (320°F).
if the pastry puffs too much at the start of cooking, cover it with another baking sheet.
2/ Pastry cream:
in a saucepan, pour the milk then bring it to a boil.
In a bowl break the eggs, then add the caster sugar, work everything together with a whisk, add the cream powder (or cornstarch), mix well, then pour the boiling milk and mix with the whisk.
Return to the saucepan and cook on the stove stirring with the whisk until it boils, remove from heat then incorporate the butter pour into a bowl and let cool.
3/ Assembly:
Cut the puff pastry into 3 strips of equal width (see photos).
Work the cold cream and add the flavoring (liquid vanilla or rum).
Take a strip of pastry, cover with half the cream, put a 2nd strip of pastry then add the rest of the cream, spread well with a spatula, then add the 3rd strip of pastry, place it carefully, press lightly then mask the edges with the cream that comes out.
Cut gently into 5 equal parts with a serrated knife, then dust with icing sugar.
Keep in the cold before serving.