Prepare the necessary ingredients.
Mix egg yolks with sugar, vanillin, and a pinch of salt. The mixture should lighten in color. Add flour and cornstarch. Mix well.
2 pcs egg, 1 pinch salt, 1 g vanillin, 12 g flour, 12 g cornstarch, 50 g sugar
In a small saucepan, heat the milk. While stirring constantly, pour the hot milk into the egg-sugar mixture in a thin stream.
250 ml milk
Return the mixture to the saucepan and cook over medium-low heat. Keep stirring until the cream comes to a boil. After boiling, cook for 1 minute. Add white chocolate and cold butter to the hot cream. Whisk vigorously until these ingredients are completely dissolved.
45 g chocolate, 15 g butter
Cover the cream with food wrap 'in contact' and let it cool down.
It's best to take the puff pastry out of the freezer the night before and put it in the refrigerator overnight. You can also defrost it on the kitchen table for 2 hours. Once the dough has thawed, roll it out into a rectangle about 3—4 cm thick. Then divide the dough into two parts. Place them on a baking sheet lined with parchment and prick them densely with a fork.
250 g puff pastry
Put the blanks in an oven preheated to 190°C for 15 minutes.
After that, turn the layers over to the other side and sprinkle with powdered sugar. Return to the oven for another 5—7 minutes, until the layers have a caramel crust. After cooling, trim the edges of the layers so that the layers of the pastries are clearly visible. Then cut each layer into three parts.
2-3 tsp powdered sugar
After cooling, trim the edges of the layers so that the layers of the pastries are clearly visible. Then cut each layer into three parts.
Whisk the cooled cream. Transfer it to a pastry bag with a nozzle. Pipe the cream onto the layers. The 'Mille-Feuille' dessert should have 3 layers and 2 layers of cream. Decorate the top of the pastry with powdered sugar or apply another layer of cream.
The dessert can be eaten immediately after assembly. It will be very crispy. Or leave it to soak for a few hours. Enjoy your meal!