Prepare the zucchini noodles with a spiralizer using the step-by-step guide above.
In a large pot, heat the olive oil over medium-high heat.
Add the minced ginger and cook, stirring, for 2 minutes.
Add the shiitake mushrooms and a tablespoon of water and cook until the mushrooms begin to sweat.
Add 7 cups of the vegetable broth, the remaining water, the red pepper flakes, tamari sauce, and 1½ cups of the chopped scallions. Bring to a boil, stirring occasionally.
Meanwhile, mix the remaining cup of vegetable broth with the corn starch and whisk until completely smooth.
While stirring the soup, slowly pour in the beaten eggs in a thin stream. Continue stirring until all of the egg is incorporated.
Slowly pour the corn starch mixture into the soup and cook for about 4-5 minutes to thicken.
Season to taste with salt & pepper (usually I add just a bit of pepper, but as long as I'm using a full-sodium vegetable broth, I don't need any extra salt).
Add the spiralized zucchini noodles to the pot and cook, stirring, for about 2 minutes, or until the noodles are just soft and flexible (remember, they'll continue cooking in your bowl!).