Season the beef strips with salt and pepper and add to the pan.Cook,stirring occasion-ally,until evenly browned. Transfer the beef to the pan with the simmering beef broth.Add the remaining 1 1/2 tablespoons oil to the hot pan used to cook the beef,add the mushrooms and cook,stirring,until they are lightly browned,3 to 5 minutes.
Remove the pan from the heat,add the brandy,and stir,scraping the bottom of the pan to loosen any browned bits. Transfer the mushrooms and their liquid to the saute’ pan with the beef. Cook,simmering,stirring occasionally,15 minutes.Add the sour cream and dill and cook another 10 minutes.Adjust the seasoning and serve.