Heat a large, heavy-bottomed nonstick skillet over medium-high heat. In a large mixing bowl, thoroughly combine the ground beef, diced white onion, beaten eggs, seasoned dry breadcrumbs, chopped fresh parsley, coarse salt, and pepper until the mixture forms a completely uniform, workable paste.

Pinch off the meat mixture and roll firmly between your palms to shape small, tight meatballs roughly 1 inch in diameter. Drop the meatballs into the hot skillet in single-layer batches and brown them aggressively for 5 to 6 minutes, turning frequently to lock in a dark, caramelized outer crust on all sides while keeping the centers slightly underdone, then transfer them to a separate clean plate.

Reduce the skillet heat to medium, leaving the rendered beef fat pooling at the bottom of the pan. Sprinkle the 4 tablespoons of all-purpose flour directly into the hot fat and whisk continuously for 1 to 2 minutes, ensuring the flour completely absorbs the lipids and toasts until it turns a deep golden brown and loses its raw aroma.

Slowly stream the beef consommé and Worcestershire sauce into the toasted roux while whisking rapidly to prevent any lumps from developing, then begin adding the room-temperature whole milk just a few tablespoons at a time. Season the liquid with salt and pepper to taste, and continue whisking without stopping for 5 minutes over medium heat until the sauce transitions into a thick, completely smooth, and glossy cream gravy.

Carefully slide the browned meatballs and any collected plate juices back into the bubbling gravy, turning them to coat them completely in the sauce. Turn the heat down to low, clamp a tight lid over the skillet, and simmer undisturbed for 15 minutes until the meatballs are cooked completely to the center and have thoroughly infused the cream sauce.

While the meatballs finish simmering, cook the egg noodles in a large pot of boiling salted water according to the package directions, then drain thoroughly and immediately toss the hot noodles with the ¼ cup of butter and 3 tablespoons of chopped parsley until melted and coated. Arrange the herbed butter noodles on a serving platter, ladle the hot meatballs and heavy gravy uniformly over the top, and shower with additional fresh parsley right before serving.