In a large bowl, combine the ground beef, panko, ketchup, mustard, Worcestershire, minced garlic, sea salt, and freshly cracked pepper, to taste. Gently combine the ingredients with your hands until well combined. Roll the mixture into small meatballs, forming about 23-25 meatballs.
Heat 1 tablespoon of oil in a large skillet over medium heat. Add the meatballs, in batches, and cook until all sides are browned, about 4-5 minutes. Transfer to a plate.
Cook the noodles in salted water, per instructions.
While the noodles are cooking, whisk together 1/2 cup beef broth and cornstarch in a small bowl; set aside.
Add the remaining oil to the skillet you cooked the meatballs in. Add the onions and mushrooms to the skillet and cook until golden brown and translucent, about 3-4 minutes. Add the minced garlic and cook, stirring constantly for 1 minute. Whisk in the remaining 1 1/2 cups beef broth, Worcestershire sauce, and ketchup until well combined, about 1-2 minutes. Bring to a boil then reduce heat and gradually whisk in cornstarch/beef broth mixture and stir until well combined. Add in the meatballs and any juices and cook until meatballs are cooked through and the sauce has thickened, about 3-4 minutes. Season with sea salt and freshly cracked pepper, to taste.
Place the drained egg noodles into a bowl and spoon the meatballs and sauce over the top. Garnish with fresh parsley and serve immediately. Enjoy.