Preheat oven to 250°F. Spread pumpkin seeds in single layer on greased foil-lined baking sheet. Bake 45 to 50 minutes or until pumpkin seeds are dry.
Mix sugar and pumpkin pie spice in small bowl. Set aside. Beat egg white in large bowl until foamy. Add dried pumpkin seeds; toss to coat. Gradually add sugar mixture, tossing to coat evenly. Spread seeds in single layer on same baking sheet.
Bake 1 hour, stirring seeds after 30 minutes. Cool slightly then break apart. Cool completely. Store in airtight container up to 2 weeks.