For the recipe you will need:
onion (large) – 1 pc.
mushrooms – 600g
olive oil – 3 tbsp.
salt, pepper (ground) – to taste
puff pastry (frozen) – 600g
sour cream – 1/2 cup.
To cook Puff pastries with mushrooms in sour cream, you need:

Finely chop mushrooms and onions. Place the onion in a pan with hot oil and fry over medium heat until golden, 4-5 minutes. Then add the mushrooms and fry everything together for another 4-5 minutes, until the moisture evaporates. Remove from heat and season with salt and pepper.

Roll out puff pastry and cut into rectangles. Put the mushroom filling on one half of each rectangle, leaving the edges free. Cover the filling with the second half of the dough and close the edges of the pies.

Transfer the mushroom pies to a greased baking sheet and make cuts on top with a knife. Lubricate with oil, send the pies to the oven preheated to 220C. Bake pies with mushrooms until browned for about 20 minutes. Serve ready pies with sour cream.