In a Dutch oven, heat olive oil over medium-high heat. Brown the sliced beef in batches until seared on all sides. Remove and set aside.

In the same pot, add chopped onion and cook until softened. Add garlic and mushrooms, cooking until mushrooms release their moisture.

Sprinkle flour over the vegetables and stir to combine. Cook for 2 minutes to eliminate the raw flour taste.

Pour in beef broth, Worcestershire sauce, Dijon mustard, paprika, salt, and black pepper. Stir well, scraping the bottom to release any browned bits.

Return the browned beef to the pot, ensuring it's submerged in the sauce. Bring to a simmer, then cover and reduce heat to low. Allow it to simmer for 1.5 to 2 hours, or until the beef is tender.

Stir in sour cream just before serving. Adjust seasoning if needed.

Serve the Dutch Oven Beef Stroganoff over cooked egg noodles, garnished with chopped fresh parsley. Enjoy the rich and comforting flavors of this classic dish!