Chocolate Praliné Galette

In a electric whisk with a dough hook, make the détrempe dough by mixing the flour, salt, water and vinegar, poured all at once. Stop mixing as soon as you obtain a completely smooth dough and form into a ball. Tightly wrap in plastic wrap and store in the refrigerator for at least 2 hours.
To make the beurre manié, in the bowl of the electric whisk with a paddle attachment, mix the room-temperature butter with the flour. As soon as you obtain an even dough, stop mixing. Create a roughly 5mm thick regular rectangle in between two sheets of baking paper using a rolling pin. Keep the beurre manié in the refrigerator until it is to be added to the dough.
After the resting time, spread the détrempe dough so that it stretches to two thirds of the surface of the butter rectangle. Place the détrempe dough on one end of the beurre manié, ensuring that the surfaces align. Fold the surface of the rolled-out butter that is not covered by détrempe dough back over rolled-out dough. Then, fold the layered surface over this. This step is known as a ‘single turn’. Rotate the dough by a quarter and then carry out a book turn.
Put the dough aside, wrap in plastic wrap and place in the refrigerator for at least 2 hours to ensure that the dough has time to rest. Carry out another single turn and book turn, making sure that you rotate the dough by a quarter each time. Put the dough aside, wrapping it in film and placing it in the refrigerator for at least 2 hours before rolling it out.

Mix the creamed butter and sugar.
Gradually add the eggs.
Finally, add the raw hazelnut flour and praliné.