Puree 6 cloves of garlic with a little anchovy until smooth.
Heat this mixture in a pot and add 2-3 liters of water. Bring to a boil and then reduce heat.
Add 1 tablespoon of soy sauce, salt to taste, and a dash of MSG. Let it simmer for about 5 minutes.
Prepare the fish stuffing: if using mackerel, fillet it and remove the bones, then finely puree with a little water.
For each stuffing ball, mix in half a tablespoon of cornstarch, salt to taste, and a pinch of white pepper. Ensure all ingredients are well mixed.
Form the mixture into balls and leave them aside for 5-6 minutes until they dry slightly on the surface. Then roll in tapioca flour to coat evenly.
Cut long beans lengthwise and cut each half into smaller pieces. Place the fish stuffing inside and top with tofu puffs, ensuring that they are well sealed.
Fry the stuffed vegetables in hot oil until they turn a golden-brown color.
Serve with the soup or with the tofu sauce alone.