VGE Soup with black truffles

Make a beef broth (like a pot-au-feu):
Simmer the shank and the ox bone with 1 peeled onion, 2 peeled and roughly cut carrots, coarse salt and 2 l water.
Do it without lid, skimming away the surface froth from time to time, and during about 2 hours.
Note: you can also add into it a bit of a chicken broth.

Meanwhile, make a vegetable "Matignon":
Peel and rinse carrots and remaining onion.
Remove the heart from the carrots.
Chop carrots and onion into very small pieces (like a for a macédoine).
Clean and cut the mushrooms into small pieces.
Fry the whole with butter over medium heat, keep a bit of "croque" (firm texture").
Pepper.

Filter out the meat broth and boil it again to reduce it by half.
Cut the shank in small pieces of flesh only, this will be your "lean beef". (Discard the rest)
When the broth has reduced, taste it, and salt the vegetables according to the degree of salt in the broth.

Preheat the oven to 220 °C (430 °F).
If your puff pastry is frozen, take it out of the freezer so that it starts to come back to room temperature.

Cut the truffle into thin slices.
Put in each small individual tureen/soup bowl/or baking bowl : 2 tbsp. of Matignon, 20 g of foie gras and 25 g of lean beef.
Add 1 tbsp. of Noilly prat, put the slices of truffle, and cover with beef broth.

In a ball beat 1 egg yolk with 1 tbsp. of with water and 1 pinch of coarse salt.

In the puff pastry sheet(s), cut out 4 "lids" a little larger than the diameter of each tureen.
Prick them lightly with a fork.
With a brush, brush the edges of each tureen with egg yolk.
Brush the remaining egg yolk on the top of each disc as a gilding.
Draw a decoration with a fork (be gentle).
Cover each tureen with its disk and close tightly.

Bake 10-15 min.
(The cooking is fast, the puff pastry should grow and take a slightly golden color).
It might burst; try to avoid it if necessary by holding it a little from time to time with a wooden spoon.

Remove from the oven and serve immediately.
Guests break the crust, and enjoy a "shoot" of truffles aromas.

This recipe was invented by the Chef Paul Bocuse in 1975 for the French President Valérie Giscard d'Estaing (VGE). It was probably inspired from the Souvarov truffle recipe.
"Cassez la croute" (break the crust/break bread) means "snack" in French. You can then figure out the play on words done by Bocuse.
Based on the size of the individual tureens, 1 or 2 puff pastry sheets might be needed. You need to be able to make 4 "lids".