Cook the noodles according to the package directions. Drain and set aside.
In a large saucepan, brown the ground beef over medium heat until no longer pink, breaking it into small pieces as it cooks; drain the fat.
Add the onion and cook until translucent (about 1 minute).
Stir in the soup, milk, sour cream, salt, and pepper into the meat.
Cook over medium heat for just a few minutes, stirring often, until hot and bubbly.
Add the noodles into the sauce and mix.
Top with the chopped parsley and serve.