Bring a large pot of salted water to a boil and cook the egg noodles according to package directions until just tender. Drain and set aside.
Melt the butter in a large skillet over medium heat. Add the diced onion and cook for 3 minutes until it softens.
Stir in the sliced mushrooms and cook for 6 to 7 minutes until they release their liquid and start to brown.
Add the minced garlic and smoked paprika. Cook for 1 minute until the garlic smells fragrant.
Sprinkle the flour over the mushroom mixture and stir for 30 seconds to coat everything evenly.
Slowly pour in the vegetable broth while stirring. Let the sauce simmer for 3 minutes until it thickens slightly.
Remove the skillet from the heat and stir in the sour cream until the sauce is smooth. Season with salt and pepper.
Divide the cooked egg noodles among four plates and spoon the mushroom sauce over the top. Finish with a sprinkle of chopped parsley.