01 - Bring a large pot of salted water to a boil. Cook egg noodles as per package directions, then drain and toss with a little butter to prevent sticking.
02 - Season the beef strips evenly with salt and pepper.
03 - Heat 1 tablespoon butter and 1 tablespoon olive oil in a large skillet over medium-high heat. Add beef in batches and sear until browned, approximately 1 minute per side. Remove and set aside.
04 - Add remaining butter and olive oil to the skillet. Sauté onions for 2–3 minutes until softened, add mushrooms and cook for 5 minutes until browned. Stir in garlic and cook for 1 more minute.
05 - Sprinkle flour over vegetables and stir well to combine. Cook for 1 minute to remove raw flour taste.
06 - Slowly whisk in beef broth, ensuring no lumps form. Add Worcestershire sauce, Dijon mustard, and paprika. Simmer for 3–4 minutes until sauce thickens.
07 - Reduce heat to low. Stir in sour cream until smooth and warmed through. Return seared beef and juices to skillet. Heat gently for 2–3 minutes without boiling to prevent curdling.
08 - Adjust seasoning if necessary. Serve stroganoff over warm egg noodles and garnish with fresh parsley.