In a pan, heat oil at medium heat. Cook mushrooms and leeks for 4 to 5 minutes while stirring.
Add baby spinaches and cook for 3 to 4 minutes while stirring. Salt and pepper. Remove form heats and let cool down.
On a floured work surface, pour down half of puff pastry in a rectangular shape of 25 cm x 20 cm (10 x 8 inches) and the other half in a rectangle of 27, 5 cm x 22,5 cm (11 po x 9 po).
Make the coulibiac by following these next steps.
Lay the smallest abaisse on a baking sheets with parchment paper. Devide half of vegetables mixture over the pastry and set aside sides of 2 cm (3/4 de po). Cover with cooked trout, then smoked trout.
Cover with rest of vegetables. Brush pastry sides with whisk egg yolk and a bit of water.
Lay down the second abaisse and press to seal the sides. Do notches on sides with a small knife. Brush the surface with egg yolk.
Slice forms (cecle, leafs, fishes) with the rest of the pastry. Lay pastry forms over coulibiac and brush with whisk egg yolk.
Oven bake for 35 minutes.
Did you know that...
Leek roots (rootlets) are edible. Clean and dry them well before frying them for a salad garnish or dip!