In a large saucepan, bring the stock to a boil over medium-high. In a medium bowl, beat the eggs to blend. Add the cheese, breadcrumbs and nutmeg, and season lightly with salt and freshly ground pepper.
Add the spinach to the boiling stock and stir until wilted, about 1 minute. Remove from the heat. Slowly drizzle in the egg mixture (do not stir or the dumplings will not form) and let stand about 3 minutes until dumplings form. Ladle the soup into bowls and garnish with freshly ground pepper and nutmeg.