Instructions:

1. Heat the vegetable oil in a large pan over medium-high heat.
2. Add the beef strips and cook until browned on all sides. Remove the beef from the pan and set aside.
3. In the same pan, add the chopped onion and cook until soft and golden brown, about 5-7 minutes.
4. Add the sliced mushrooms and minced garlic, cooking for another 5 minutes until the mushrooms are tender.
5. Stir in the paprika, beef broth, and Dijon mustard, bringing the mixture to a simmer.
6. Return the browned beef to the pan, stirring to combine. Cook for another 5 minutes to allow the flavors to meld.
7. Reduce the heat to low and stir in the sour cream. If the sauce needs thickening, sprinkle in the flour and stir well.
8. Season with salt and pepper to taste.
9. Serve the beef stroganoff hot, garnished with fresh parsley, alongside cooked egg noodles or rice.