Coulibiac de Saumon — Salmon in Brioche with Rice and Eggs

Ingredients

• 800 g salmon fillets, two equal fillets, skinned and seasoned
• 200 g long-grain rice, cooked as pilaf
• 250 g mushrooms, finely chopped, worked into a dry duxelles
• 4 eggs, hard-boiled, cooled, and sliced
• 1 quantity brioche dough, prepared in advance, chilled; sufficient to roll a large rectangle 5 mm thick
• 1 egg, beaten, for egg wash
• For the vesiga (optional)
• 50 g vesiga, dried sturgeon marrow cord; soaked then simmered until translucent and gelatinous; omitted in modern versions
• For the sauce
• 250 ml beurre blanc or sauce mousseline, prepared separately; served on the side

Method

1. 1
   Cook the rice as a pilaf and spread it on a tray to cool completely. Work the mushrooms over high heat, pressing out all moisture, until the duxelles is entirely dry and holds its shape when pressed. Hard-boil the eggs, cool them under cold water, and slice evenly. All components must be cold before assembly — no residual steam should enter the brioche.
2. 2
   Season the salmon fillets. Heat a dry pan until very hot and sear each fillet on one side only, for no more than 90 seconds, until that face is lightly coloured. Remove immediately. The flesh on the unseared side must still be completely raw — the salmon finishes inside the brioche, and any further cooking at this stage will result in an overcooked centre at the table.
3. 3
   Roll the chilled brioche dough on a lightly floured surface to a large rectangle, 5 mm thick — thin enough to encase cleanly, thick enough to hold without tearing under the weight of the filling. Lay it on a sheet of parchment paper.
4. 4
   This is where the coulibiac lives or dies. Layer the filling with strict symmetry along the centre of the dough: first a bed of rice, then the sliced eggs, then the first salmon fillet seared-side down, then the duxelles pressed flat, then the second fillet seared-side up, then the remaining rice. Each layer must be level, compact, and distinct — the cross-section when sliced is the measure of the dish. If vesiga has been prepared, incorporate it with the duxelles layer.
5. 5
   Brush the exposed edges of the brioche with egg wash. Fold the long sides up and over the filling, then fold and press the ends firmly to seal, as one would seal an envelope. Invert the entire package onto a parchment-lined baking sheet so that the seam lies on the bottom. The outer surface should be smooth and taut, showing no cracks or thin patches.
6. 6
   Cut a small steam hole in the top of the brioche and insert a small foil chimney. Brush the entire surface generously with egg wash. Allow the coulibiac to rest at room temperature for 15 minutes while the oven reaches 190°C, so the dough relaxes and begins a gentle final proof.
7. 7
   Bake at 190°C for 35 to 40 minutes. The brioche is ready when it is deeply golden on all visible surfaces and an instant-read thermometer inserted through the foil chimney to the salmon's centre reads 55°C. The colour must be uniform — pale patches indicate underbaked dough concealing an underset filling.
8. 8
   Remove from the oven and rest on the baking sheet for 10 minutes without cutting. The filling consolidates and the internal temperature continues to rise slightly; slicing too early will cause the layers to spill and collapse. Slice into thick rounds at the table — each cross-section should reveal distinct, colourful strata of golden brioche, white rice, egg, salmon, and dark duxelles. Serve with beurre blanc or sauce mousseline passed separately.