Chocolate & pistachio king's cake

Fourth and probably last king’s cake for this year, with an association that always pleases a lot: chocolate & pistachio. A well-flavored frangipane, whole pistachios and a bit of crunchy cocoa nibs, all in a crispy puff pastry, that's the program!
 
 
 
 Prep time : 1h30, a lot of rest and 40 minutes cooking
 For a 25cm galette :

 

The puff pastry :  

375g T55 flour
 7g salt
 185g water
 50g butter
 200g butter
 
 With these quantities you will have enough to make 2 galettes. You can of course freeze dough pieces for future use.

 Melt the 50g of butter. Mix it with the water, then add the salt and the flour. Knead at low speed for 2 to 3 minutes, then form a ball, spread it into a small rectangle and put it in the refrigerator for at least 45 minutes.
 
 
 
 
 After resting in the refrigerator, work on the butter with a rolling pin (the goal is not to make it creamy, but rather to give it an elastic texture that doesn't break. To do this, tap the butter with the rolling pin, then fold it over and repeat until you get the right texture) then spread it out in a sheet of parchment paper folded into a square.
 
 
 
 Next, spread the dough into a rectangle the same width and three times as long as the butter.
 
 
 
 Put the butter in the middle.
 
 
 
 Fold the dough over the butter.
 
 
 
 Turn the dough a quarter turn, then flatten the top and bottom so the dough doesn't warp as you roll it out.
 
 
 
 
 Roll out the dough into a large rectangle.
 
 
 
 Fold the dough as shown in the photo below: fold a large portion of the dough from the top to the bottom, and a small portion from the bottom to the top. The two parts should not overlap.
 
 
 
 Fold the dough in half again:
 
 
 
 Turn the dough a quarter turn, then repeat the same process (roll out, fold in).
 
 
 
 
 
 
 
 
 You have completed two double turns. At this point, wrap the dough in cling film and place it in the refrigerator for 30 to 45 minutes (if necessary, if the dough warms up too quickly, you can chill it between rounds).
 After resting, repeat the same process: make two double turns, then put the dough in the refrigerator for at least 30 minutes.
 
 

The pastry cream :

 75g milk
 15g egg
 10g sugar
 5g cornstarch
 25g Caraïbes dark chocolate (66% cocoa)
 
 Heat the milk.
 Whisk the egg with the sugar and cornstarch.
 
 
 
 
 Pour the hot milk over it, then pour it back into the pan and thicken over medium heat, stirring constantly.
 
 
 
 Pour the cream on the chocolate, mix well then put a plastic wrap on the cream and put it in the refrigerator.
 
 
 
 

The pistachio cream :

 50g butter
 50g powdered sugar
 50g pistachio powder
 10g flour
 1 egg
 
 Mix the butter with the powdered sugar. Then add the pecan powder, then the flour and finish with the egg.
 
 
 
 

The frangipane :

 35g pistachios
 10g cocoa nibs (or alternatively dark chocolate chips)
 
 Soften the custard with a whisk, then mix it with the pistachio cream.
Then add the pistachios and cocoa nibs
 
 
 
 

Le montage et la cuisson :

 

Assembly and cooking :

 1 egg and a little cream for the egg wash
 
 Cut your puff pastry into 4 equal pieces. If you are making only one galette, you can freeze two of the pieces. 
 Roll out one of the two pieces of pastry so that you can make a circle about 25cm in diameter. Spread the frangipane over the dough, leaving about 2cm free all around. Add the bean/fève at this point by pushing it into the cream.
 Spread a little water around the edge of the dough (so that the second dough sticks to the first). Roll out the second dough, then cover the frangipane with it. Press lightly on the edges so that the two doughs stick together and don't leak during baking.
 Cut out the dough with a sharp knife or cutter to make a circle.
 
 
 
 
 Put the galette in the refrigerator for at least 1h30 (you can leave it overnight). 
 Then, turn the cake over, and put egg wash on it a first time with the beaten egg mixed with a drop of cream (be careful to spread the egg wash well and not to let it run down the sides of the cake, as this would prevent the puff pastry from developing during cooking). Put it in the refrigerator for 30 minutes.
 
 Then, spread some egg wash on it a second time and put it in the refrigerator again for 30 minutes. 
 Finally, use the blade of a knife to draw the desired pattern. Pierce it in 3 or 4 places on the surface of the cake so that the steam can escape during cooking and the galette does not explode.
 
 
 
 Bake it in the preheated oven at 180°C for 35 to 40 minutes, then let it cool on a rack and enjoy!