Cook the Beef: In a large skillet, melt 1 tbsp of butter over medium-high heat. Add the beef strips, season with salt and pepper, and cook until browned (about 3-4 minutes). Remove from the skillet and set aside.
Sauté the Veggies: In the same skillet, melt the remaining butter. Add the onions and cook until softened (about 2 minutes). Add garlic and mushrooms, cooking for another 5 minutes until mushrooms are golden.
Make the Sauce: Sprinkle the flour over the mushroom mixture and stir for 1 minute. Gradually add the beef broth, stirring until the sauce thickens (about 3-4 minutes).
Combine: Stir in the sour cream and return the beef to the skillet. Let everything simmer together for 2-3 minutes. Adjust seasoning with salt and pepper.
Serve: Serve over egg noodles or rice, and garnish with fresh parsley for that perfect finishing touch!
This creamy, flavorful dish will have your family asking for seconds!
