Bring a kettle or a medium saucepan of water to a boil for the rice noodles.

Put the dried rice noodles into a large heatproof bowl.

Pour the boiling water over the noodles until they are fully covered.

Soak the noodles for 6 to 8 minutes, until they bend easily but still feel a little firm in the center.

Drain the noodles in a colander, rinse them briefly under cool water to stop the cooking, and set them aside.

Set a large soup pot on the stove over medium heat and add the neutral oil.

Add the sliced mushrooms to the pot and spread them into an even layer. Cook for 4 to 5 minutes, stirring now and then, until they shrink, give off their moisture, and start to brown.

Add the carrots, the scallion whites, and the grated ginger to the pot. Cook for 2 minutes, stirring often, until the ginger smells strong and the carrots begin to soften.

Pour the vegetable broth and the water into the pot and raise the heat to medium-high.

Bring the broth to a gentle boil, then stir in the soy sauce, toasted sesame oil, and rice vinegar.

Add the spinach to the pot by handfuls, stirring after each handful so it fits. Cook for 1 to 2 minutes, until the spinach wilts into the broth.

Crack the eggs into a small bowl and beat them with a fork until the whites and yolks are fully mixed.