1.Rinse a piece of meat in warm water. Peel an onion.
2.Cut the meat into thin slices (approximately 5 mm) across the fibres of the tenderloin.
3.Cut each meat slice with a sharp knife into strips.
4.Chop a peeled onion into quarters.
5.Warm up a pan with vegetable oil on very high heat. Fry small portions of meat strips (make several settings) until golden brown.
6.Put it to cool in a bowl.
7.Immediately after the meat, load the chopped onion in the pan. The pan should not be pre-washed. Fry the onions for a couple of minutes on medim heat in the remains of the oil after the previous meat contents.
8.Pour the onions with the entire portion of sour cream, add tomato sauce, salt, pepper.
9.Intensively stir a spoonful of flour in half a glass of water. Pour flour mixture into the pan. Mix. Put the meat strips in a resulting sour-cream sauce. Mix with a spoon. Continue to simmer for five minutes on medium heat, closing the lid.
10.As it was mentioned above, Beef Stroganoff can be served with your favorite garnish (we propose to fry the potatoes for this purpose).