1.In a large bowl, mix together the ground pork, all but 1 tablespoon of the green onions, egg, flour, salt, and pepper. Once the ingredients are well combined, form 1-inch meatballs and place onto a plate.
2.Heat the olive oil in a Dutch oven over medium-high heat. Add the garlic and onions and sauté just until they are soft and fragrant, about 1 to 2 minutes.
3.Pour in the broth and fish sauce, then bring to a boil. Once the liquid is boiling, gently add the meatballs one at a time and cook in the boiling liquid for about 10 minutes, just until the meatballs are cooked through.
4.Add the noodles and cook for about 3 minutes, stirring regularly, just until the noodles are cooked. Turn off the heat and serve the soup. Garnish with the remaining green onions.