Nana's Beef and Mushroom Stroganoff

Combine 1 tablespoon of flour and 1/2 teaspoon of salt in a spacious, leak-proof plastic container; thoroughly mix. Add the beef and shake vigorously to evenly coat.

Heat 2 tablespoons of butter in a large, flat skillet over a medium-high heat setting. Add the beef and cook until browned on both sides, approximately 3 minutes per side. Introduce mushrooms, onion, and garlic into the skillet; cook and stir until the garlic emits a fragrant aroma, taking around 3 to 4 minutes. Transfer the beef mixture to a separate container; retain the rich, savory sauce in the skillet.

Melt the remaining 2 tablespoons of butter in the same skillet over a lower heat setting. Add 3 tablespoons of flour; cook and stir until it forms a smooth, even consistency. Gradually incorporate tomato paste into the mixture; whisk in beef stock until well combined. Cook and stir constantly, allowing the sauce to thicken and bubble, approximately 5 minutes.

Return the beef mixture to the skillet; stir to coat with the sauce evenly. Lower the heat to a very low setting; simmer until the beef becomes tender, spanning 2 to 3 hours. The longer the beef cooks, the more tender it will be. Just before serving, stir in sour cream and white wine into the beef mixture; heat through until warm. Avoid boiling the dish at any cost.