01 -
Slice the beef thinly against the grain, chop the onion, and clean and slice the mushrooms.
02 -
Heat olive oil in a large skillet over medium-high heat. Sauté the beef in batches until browned, about 3 to 4 minutes per batch. Remove beef from skillet and set aside.
03 -
Add additional olive oil if necessary. Sauté the chopped onions in the same skillet until translucent, about 3 minutes. Add the sliced mushrooms and cook until golden brown, approximately 5 minutes.
04 -
Return the browned beef to the skillet. Stir in Worcestershire sauce, Dijon mustard, and beef broth. Simmer over medium heat for 10 minutes, allowing the sauce to thicken.
05 -
Remove skillet from heat and fold in sour cream until fully blended. Adjust seasoning with salt and black pepper as desired.
06 -
Serve hot over prepared egg noodles or steamed rice.