Sear the Beef:

• Heat 1 tablespoon of butter in a large skillet over medium-high heat. Once hot, add the beef strips in batches, searing them for 1-2 minutes per side until browned. Remove the beef from the skillet and set it aside.

Sauté the Aromatics:

• In the same skillet, add the remaining 1 tablespoon of butter. Add the chopped onions and minced garlic, cooking for 3-4 minutes until they soften and become fragrant.

Cook the Mushrooms:

• Add the sliced mushrooms to the skillet and sauté for an additional 4-5 minutes, until they release their moisture and become golden brown.

Create the Sauce:

• Sprinkle the flour over the vegetables and stir to form a roux. Cook for 1 minute to eliminate the raw flour taste. Gradually add the beef broth while stirring to prevent lumps. If using, stir in the paprika and Dijon mustard for added flavor.

Simmer and Thicken:

• Allow the sauce to simmer for 4-5 minutes, until it begins to thicken. Return the seared beef and any juices back into the skillet, stirring to combine.

Finish the Dish:

• Lower the heat and stir in the sour cream until the sauce is smooth and creamy. Season with salt and pepper to taste. Let it heat through, but avoid boiling to maintain a smooth texture.

Serve:

• Serve the Beef Stroganoff over a bed of egg noodles, rice, or mashed potatoes. Garnish with freshly chopped parsley.