In a large bowl, combine all meatball ingredients. Mix well and shape into 1-inch diameter meatballs.
Heat olive oil in a large skillet over medium heat. Brown meatballs on all sides (2-3 minutes per side). Remove and set aside.
In the same skillet, cook mushrooms until browned and tender, about 5 minutes.
Sprinkle flour over mushrooms and cook for 1 minute, stirring constantly.
Gradually stir in beef broth and water, ensuring no flour lumps remain. Bring to a simmer.
Return meatballs to the skillet. Cover and simmer for 10-15 minutes, or until meatballs are cooked through.
Season with salt and pepper to taste.
Serve Salisbury steak meatballs with mushroom gravy over mashed potatoes, rice, or pasta.
