Cut the asparagus into small pieces. Soak the glass noodles until soft. Cut the tofu into cubes. Slice the mushrooms thinly and add them to a pot of boiling water. Season with 3 tablespoons soy sauce, 1 teaspoon vegetarian bouillon, and 1 tablespoon sugar. Adjust seasoning to taste.

Add the asparagus. When the water returns to a boil, add the tofu, then the glass noodles. Stir gently, then turn off the heat.

Ladle the soup into bowls. Top with chopped cilantro and a sprinkle of black pepper.