In a medium saucepan, bring the stock to a simmer. Add 6 tablespoons of the green onions, the spinach, mushrooms, soy and white pepper. Return to a bare simmer and cook for 3 minutes. Stirring with a fork or chopstick, gradually add the eggs in a slow steady stream. Cook until the eggs are set, stirring to create shreds or ribbons of the eggs, 1 minute.
Remove from the heat. Ladle into bowls, garnish with the remaining 2 tablespoons of green onions, and serve immediately.
