In a small bowl, mix the Panko breadcrumbs and milk, allowing to soak for a minute. Meanwhile, prepare a baking sheet with parchment paper or foil.
In a large bowl, combine the Panko mixture, beef, garlic, eggs, 1 Tbsp Worcestershire sauce, Italian seasoning, salt and pepper. Mix to combine (the best way is to use your hands!).
Form beef mixture into 18 2-Tbsp portions, and place on the prepared baking sheet.
In a large skillet, hit 1 Tbsp oil over medium heat until oil is shimmering. Arrange the meatballs in one layer, and brown on all sides (about 3 minutes each). Place on a plate.
Pour remaining oil into the skillet, and heat to shimmering. Add mushrooms and garlic to the skillet. Cook, stirring frequently for 3 minutes, or until the mushrooms are soft and have released their liquid. Remove with a slotted spoon to the meatball plate.
Melt butter in the skillet, and sprinkle in flour. Cook the mixture for at least 2 minutes, whisking constantly. Slowly add the broth and remaining Worcestershire sauce, and bring to a boil, whisking frequently. Allow to simmer 3-5 minutes, or until it begins to thicken.
Add browned meatballs and mushrooms, and cook for an additional 8-10 minutes. (If the gravy gets too thick, add a little more broth to thin it out.)
Salt and pepper to tasted. Serve hot over mashed potatoes, cooked egg noodles, or on their own.