Combine 1/4 cup cream and 1/4 cup bread crumbs in a small mixing bowl and set aside
In a large pan saute the garlic and onions in 1 tbsp butter.
In a large mixing bowl add the beef, oregano, salt, pepper, egg, cream and breadcrumb mixture.
When the onions are translucent, add them with any leftover butter to the meat. Mix everything together thoroughly.
Heat some olive oil and melt another tbsp butter in the large pan on medium high. Form the meat into about 20 - 24 golf ball sized meatballs, brown them on 2 sides in the pan in 2 batches. You want them to be a deep brown on both sides with lots of brown stuff stuck to the bottom of the pan. This should take about 2 minutes for each side.
Remove the meatballs from the pan when browned on both sides, leaving any juices in the pan.
Deglaze the pan with the white wine and use a wooden spoon to scrape up all the brown bits.
Melt 4 tbsp butter in the pan, then add the flour and whisk vigorously to create the roux. Whisk in the beef broth and bring to a simmer. Whisk in the cream, worchestershire sauce and mustard.
Bring the gravy to a full boil, then reduce heat to medium. Return the meatballs to the gravy, cover and cook for 20 minutes or more.
Serve over egg noodles or mashed potatoes