In a large bowl, combine the beef, egg, sour cream and Worcestershire sauce. Mix in soup mix, cheese, and bread crumbs. Form mixture into a loaf, and place in a 9x5 inch loaf pan. Cover with foil.
Bake at 375 degrees F (190 degrees C) for 45 minutes. Remove foil and continue baking for another 10 to 15 minutes. Let stand 5 to 10 minutes before serving for easier slicing.
