Check it out below:
400 g oyster mushroom, 5 tbsp cooking oil, 1 medium-sized onion, 300 g soft sheep's cheese, 1 packet of puff pastry, salt, pepper to taste, 1 tsp thyme, 1 egg yolk, butter
Finely chop the onion and dice the oyster mushrooms. Heat the cooking oil in a pan, then add the chopped onion and sauté over low heat until softened. Add the mushrooms to the pan and sauté over high heat until they are nicely browned. Remove the pan from the heat, season the mushrooms with salt and pepper, then add the cheese and thyme. Return the pan to the heat and mix everything together over low heat for about a minute. Let it cool. Roll out the puff pastry, which had been taken out of the refrigerator and allowed to warm up, and cut it into 3 equal parts. Place the first sheet in a greased baking dish and evently spread half of the sheep's cheese filling over it. Place the second sheet on top and spread the remaining filling over it. Finally, cover the pastry with the last sheet and brush with the egg yolk. Bake the pie in a preheated oven at 180°C for 13-15 minutes until the top is golden brown. The pie is delicious served warm or cold.