Wash and peel the carrots and slice them with a cucumber slicer. Chop the onion into small cubes. Drain the mushrooms. Stew everything in a pan with a little oil.
Mix the flour, paprika, salt and pepper together. Turn the meat in it. Move the vegetables to the side in the pan and fry the meat. Pour in the stock and cook, covered, for 20 minutes. Stir in sour cream.