Wash the tomatoes. Dice 7 oz (200 grams) and cut the remaining 3.5 oz (100 grams) into wedges. Wash and chop the green onions, keeping the white parts separate. In a bowl, combine the shrimp, pork, and egg yolk. Add 1 tablespoon seasoning powder, 1 tablespoon sugar, 1 tablespoon fish sauce, 1 tablespoon annatto oil, and 1/3 tablespoon black pepper. Mix well and let marinate for 15 minutes.

To make crispy pork fat: Wash the pork fat, drain, and cut into cubes (not too small or too large). Place the fat in a pan with a splash of water and cook over heat until golden and crispy. Remove and drain on a rack.

To fry the tofu: Cut the tofu into your preferred size. Fry the tofu in the rendered pork fat until golden and crispy. Remove and drain on a rack.

Add 4 tablespoons of rendered pork fat to a pot and heat. Sauté the white parts of the green onions until fragrant, then add the diced tomatoes. Add 1 tablespoon seasoning powder, 1 tablespoon sugar, and 2 tablespoons fish sauce. Stir until the tomatoes soften, then pour in 7 1/4 cups water (1.7 liters) and bring to a boil.

When the broth is boiling, shape the shrimp and pork mixture into small balls and drop them into the pot. Cook until the meatballs are done.

Once the meatballs are cooked, add the fried tofu and tomato wedges. Stir in 2 tablespoons fermented shrimp paste. Bring the broth back to a boil, adjust the seasoning to taste, then reduce the heat to keep warm.