Combine all of the meatball ingredients together until you have an even consistency and texture. 

Form small balls that are about 1.5 inches, this should make about 40 in that size. Set them onto a tray while you make the rest. 

Heat a deep stainless pan, ideally 12 to 14 inches, to medium high heat and melt about half of the butter. 

Once the butter has started to bubble you can add in about 10 to 14 meatballs, brown on all sides, about 1-2 minutes per side, about 8-10 minutes total. 

Transfer to a clean dish and cover while you repeat in batches with the rest of the meatballs. 

Once all the meatballs are done you can scrape the bottom of the pan for all of the flavor filled bits. 

The bottom of the pan should also have a few tablespoons of fat and butter left over in it, if needed you can add a little more. 

Carefully whisk the flour into the fat, let it bubble for about 1 full minute. This will help cook off the flour taste in the rue. 

Slowly start to add in the beef broth, continuing to whisk until you have a thin gravy. 

Add all of the meatballs back into the pan, some will likely be up on top a bit, just rotate as they simmer.

Let the sauce reduce while the meatballs finish cooking, uncovered, for about 10 to 15 minutes.

At this time you can slowly add in the heavy cream or sour cream and gently swirl to mix it in.