For the filling, prepare the thigh fillet, cut it into a small cube. I had frozen mushrooms, and if you use fresh ones, then wash them and also cut them. Grate the cheese on a fine grater. In a frying pan, first fry the fillet, then add the mushrooms, mushroom seasoning and pepper and fry until tender. Pour in the sour cream, add salt, add chopped garlic and warm up together.