Prepare noodles according to package directions. When they are cooked, drain and set aside.
In a large skillet over medium-high heat, brown the beef, breaking it up into pieces as it cooks.
Add the onions to the pan and sauté, stirring frequently, until translucent and soft – about 5 minutes.
Sprinkle the flour over the beef and onion, stirring to evenly coat and allow the flour to absorb oil.
Add the beef broth, sour cream, Dijon, Worcestershire, and beef bouillon to the pan. Stir until combined, and allow the sauce to simmer until thickened.
Toss the noodles to coat evenly with the sauce. Adjust seasoning with salt & pepper and garnish with parsley before serving.