Heat a small amount of vegetable oil in a frying pan and fry the onion until Golden.
Add the meat to the pan and, turning the meat pieces, fry on all sides for 5-7 minutes.Add oyster mushrooms. Stir and fry everything together for another 2-3 minutes.
Season with salt and black pepper to taste, add spices-thyme and oregano. Stir.
Transfer, if necessary, the meat with oyster mushrooms to a convenient stew pot. Add sour cream, pour in water, mix gently and put on the fire, bring to a boil, then reduce the heat to a minimum and simmer until the meat is ready and soft, do not forget to stir periodically and of course adjust for salt/pepper if necessary.