Preheat oven to 325 degrees F. Line a baking sheet with parchment paper or foil. Set aside.
In a medium bowl, combine egg white, sugar, oil, lemon peel, kosher salt, cinnamon, nutmeg, paprika and chili flakes, whisk until egg white is frothy and sugar is nearly dissolved. Add pumpkin seeds, toss gently to coat.
Spread pumpkin seeds evenly on the prepared baking sheet. Bake for 20 to 25 minutes or until pumpkin seeds are dry and crisp. Cool completely and brake into pieces.