Get the beef stock hot
Making the stock warmer makes it easier to make the roux thicker
Put medium heat on a big pan
Add the meatballs that have been baked and cook them until they're nice and warm
You want the meatballs to spread their tasty vibes all over the pan
When the meatballs are warm, take them out and set them away
Put the butter in the pan and let it melt
Then, add the flour and cook it for a few minutes in the butter
Add the hot stock to the pan and stir or whisk it well
It needs to quickly turn into a sauce
After that, add the cream, Dijon mustard, and Worcestershire sauce if you want
Mix everything together
Put the meatballs back in the pan and cook them slowly until the gravy gets thick