Stuffed salmon in dough

Ingredients:

Mushroom stuffing with shrimps

• 1 tbsp unsalted butter
• 1/3 cup thinly sliced ​​shallots
• 220 g mushrooms (chanterelles, oyster mushrooms, champignons, shiitake or a mixture of them), thinly sliced ​​(about 3 cups)
• 110 g shrimp, peeled and cut into 1 cm pieces.
• 1/4 teaspoon salt
• 1/4 tsp freshly ground black pepper
• 3 tbsp. l. chopped chives
• 1 small salmon with head (about 2.3 kg) to yield 1.1 kg fillet
• 1 package of store-bought puff pastry
• 1 large egg

Foamy lemon sauce

• 1 cup chicken broth + 0.5 cup
• 0.5 tsp potato starch
• 3 large egg yolks
• 1/4 teaspoon salt
• A pinch of cayenne pepper
• 2 tablespoons lemon juice

Preparation:

1. Filling:
   
   Heat 1 tablespoon of butter in a skillet. Add the shallots. Sauté for about 1 minute, until softened, then add the mushrooms and cook over medium-high heat until they release their juices. Once the juices have evaporated and the mixture begins to sizzle again, add the shrimp and cook for about 1 minute, until the pieces turn white. Season with salt, pepper, and sprinkle with green onions. Let the filling cool.
   
2. When ready to assemble, line a large baking sheet with parchment paper. Roll out the dough into a 40cm square. Cut a 40cm long, 12-15cm wide strip of dough and lay it diagonally on the parchment paper. Place one salmon fillet on top and lightly season with salt and pepper. Spread the cooled filling evenly over the top, then top with a second salmon fillet.
3. Place the fillets so that the thinner portion on the bottom rests on the larger, thicker portion on top (tail to head and head to tail), ensuring the shape and thickness of the fish are uniform. This will ensure even cooking.
4. Place the remaining, wider strip of dough over a rolling pin and transfer it to the fish. Brush flour off the surface of the dough and press it along the edges, shaping it into the fish. The larger top layer of dough should adhere to the bottom layer of dough along the edge. Gently press the two layers of dough along the edges to ensure they are tightly sealed, then place in the freezer for about 10 minutes to set. This will make decorating the fish easier.
5. Preheat oven to 190°C.
6. After 10 minutes, remove the fish from the freezer and trim away any excess dough around the edges, creating the outline of a fish with dorsal fins and a tail made from scraps of dough. Create gills from a strip of trimmed dough, cut out a circle of dough, and attach an eye. Continue decorating as desired.
7. Crack a whole egg into a small bowl and remove about half the white. Beat the remaining egg in the bowl with a fork. Brush the dough with the egg wash. Holding the tip of a pastry bag (large end down) at an angle, press it lightly into the dough to create scale-like marks.
8. Bake in the oven at 190°C for 35-40 minutes. Remove the fish from the oven and, uncovered, place it in a warm place while you prepare the sauce.
9. Foamy lemon sauce:
   
   Combine 1 cup of chicken broth with potato starch in a saucepan and bring to a boil. Whisk the egg yolks with the remaining broth in a bowl, then pour into the hot broth and whisk constantly over medium heat for about 2 minutes, or until the sauce thickens and foams, but do not let it boil. The sauce should reach a temperature of 180°F (82°C). Add salt and cayenne pepper, then remove the saucepan from the heat, stir in the lemon juice, and set aside. The sauce should have doubled in volume.
   
10. Using two large spatulas, transfer the fish to a serving platter. Before serving, slice into 3-4 cm thick slices and arrange on warmed plates. Drizzle the sauce over the slices and serve immediately.