In a large skillet, brown and crumble the ground beef, onion, and garlic over medium heat until just a little pink remains. Drain, if needed, and return to skillet.
Add mushrooms, salt, and pepper. Cook 4-5 minutes, or until mushrooms start to soften.
In a small bowl, combine beef broth, Worcestershire sauce, and paprika. Whisk in flour until no lumps remain.
Add broth mixture to beef mixture and stir. Bring to a boil, then cover and simmer on low heat for 5-7 minutes, or until slightly thickened. Remove from heat and stir in sour cream.
Serve over hot egg noodles and garnish with parsley, if desired.