Step 1: Prepare the Beef. Pat the beef dry with paper towels to ensure it browns well. In a medium bowl, combine the flour and salt, then add the beef pieces and toss to coat evenly. The flour helps the beef develop a nice sear and slightly thickens the sauce later.

Step 2: Brown the Beef. Melt the butter in a large skillet over medium heat. Add the floured beef pieces in a single layer and cook without stirring for about 2–3 minutes, allowing a golden crust to form on one side. Gently flip the pieces and cook for another 2–3 minutes until browned on the other side. Remove the beef from the skillet and set aside, leaving the flavorful drippings behind.

Step 3: Sauté the Vegetables. In the same skillet, add the chopped onion and sliced mushrooms. Sauté for 4–5 minutes, stirring occasionally, until the onions are soft and translucent and the mushrooms are tender and lightly browned. This builds the flavor base for your sauce.

Step 4: Make the Sauce. Add the browned beef back into the skillet along with the cream of mushroom soup, water, tomato paste, and garlic powder. Stir well to combine and ensure all the beef pieces are coated in the creamy sauce.

Step 5: Simmer Gently. Reduce the heat to low and let the mixture simmer for 5–6 minutes, stirring occasionally, until the beef is cooked through but still tender. The sauce will thicken slightly as it simmers.

Step 6: Add the Sour Cream. Remove the skillet from the heat and stir in the sour cream. Adding it last ensures it blends smoothly without curdling. Mix gently until the sauce is creamy and uniform in texture.

Step 7: Serve. Serve the stroganoff immediately over a bed of hot egg noodles, rice, or mashed potatoes. Garnish with freshly chopped parsley for a touch of color and freshness.