Heat olive oil in a pan over medium heat.
Add beef, add salt and pepper.
Cook for 3 minutes until brown, then remove.
Melt butter in the same pan.
Cook onions and garlic until soft.
Add mushrooms and cook for 5 minutes.
Sprinkle flour over mushrooms, mix well.
Add beef broth and Worcestershire sauce.
Stir and cook for 3 minutes until thicker.
Put beef back in the pan, mix well.
Turn heat low, add sour cream, and mix.
Cook for 2 minutes without boiling.
Serve over cooked noodles, add parsley on top.