Add the oil to a large pot over a medium-high heat. Add the mushrooms, scallions, green onion,ginger and garlic. Cook and stir for 1-2 minutes.
Add the chicken, tofu, broth, red pepper flakes, vinegar and coconut aminos (or soy sauce). Bring to a boil, then reduce the heat and allow to simmer for about 10 minutes or until the mushrooms are tender.
Lightly whip the eggs in a separate bowl with a pourable spout.
Stir the soup in a circular motion in one direction, then drizzle in the eggs in a thin and slow pour while continuing to stir the soup.
Sample the soup and add more red pepper flakes, coconut aminos, vinegar, as needed Stir in ground pepper
Serve hot. Garnish the hot and sour soup with chopped chives and cilantro.You can add a splash of sriracha on top for more spice and a nice look.
Notes: If you wish to have a thicker soup, you can use 2 tablespoons of arrowroot flour whisked with water in a small bowl. Mix into the soup after it has been simmering, before you add the eggs.