High-Heat Beef Sear: Heat 1 tablespoon of olive oil and 1 tablespoon of butter in a large heavy skillet over high heat. Season beef strips generously with salt and pepper. Add beef in a single layer and sear undisturbed for 1-2 minutes per side until deeply browned on the edges but still pink inside. Immediately transfer to a plate (do not overcook).
Caramelize Mushrooms & Onions: Add remaining oil and 1 tablespoon butter to the hot skillet. Add sliced cremini mushrooms and diced onions. Sauté for 6-8 minutes until golden-brown, caramelized, and fragrant. Stir in minced garlic and cook for 1 minute.
Build the Velvety Roux: Sprinkle flour over the cooked vegetables, stirring continuously for 1-2 minutes to toast the flour.
Deglaze & Simmer Gravy: Slowly whisk in the halal beef broth, Dijon mustard, and Worcestershire sauce, scraping up all flavorful brown bits from the skillet bottom. Simmer gently for 4-5 minutes until the gravy turns rich, glossy, and thick.
Temper & Fold Sour Cream: Remove skillet from direct heat. Whisk in room-temperature sour cream until completely smooth and velvety.
Return Beef & Juices: Return seared beef along with any resting juices into the warm creamy gravy. Let rest in the warm sauce for 2 minutes to heat through without boiling (keeps meat extraordinarily tender).
Serve over Egg Noodles: Boil egg noodles according to package instructions until tender; drain and toss with remaining tablespoon of butter. Ladle generous mounds of beef stroganoff over noodles, shower with fresh dill, parsley, and cracked black pepper.