Russian Pan-Fried Potatoes with Mushrooms

"This dish is quite ordinary so it is suitable for a nourishing lunch of the family. Potato is perfectly combined with any kind of mushrooms. Today we use oyster mushrooms, they do not lose their shape, do not break up, remain juicy and elastic. All ingredients are fried in one frying pan, but as oyster mushrooms emit a lot of juice during frying, potatoes can be sometimes prepared separately, and then onions and mushrooms are added to it."