In a large bowl, combine ground beef, breadcrumbs, eggs, sautéed onions, minced garlic, Worcestershire sauce, milk, and a dash of salt and pepper. Mix until just combined. Shape into meatballs, about 1 inch in diameter.

Heat a large skillet over medium heat and add oil. Sauté the meatballs for 8-10 minutes until golden brown on all sides and cooked through.

In the same skillet, melt butter over medium heat. Whisk in flour to create a roux, cooking for 1-2 minutes. Gradually add beef broth, stirring continuously. Let simmer for 5-7 minutes until thickened.

Cook pasta according to package instructions but drain 2 minutes early. Combine pasta with creamy sauce in a large mixing bowl, and gently fold in browned meatballs.

Preheat oven to 350°F (175°C). Transfer mixture into a greased casserole dish and spread evenly. Optionally sprinkle cheese on top. Bake for 25-30 minutes until hot and bubbly.

Remove from oven and let rest for 5-10 minutes before serving. Spoon into bowls and enjoy.