Remove meatballs when they are cooked all the way through. If all the oil has cooked out, drizzle a very small amount, like no more than a teaspoon or two. Sprinkle the flour in the skillet and allow to cook for about 3-5 minutes. It should be a golden brown color and not burned. With a whisk, add beef broth and mix until all flour and the yummy bits on the bottom of the skillet are incorporated. Add the sour cream and mix thoroughly, then add the milk and nutmeg and continue to whisk to everything is mixed. Add meatballs back to the skillet, cover and simmer on medium-low, allowing them to warm back up. Pour on top of hot, buttered egg noodles. Enjoy!