Preheat oven to 250 degrees.
Pop popcorn into a very large bowl.
Melt butter in a medium saucepan over medium heat. Stir in brown sugar, corn syrup, cinnamon, pumpkin pie spice and salt.Bring mixture to a boil and allow to boil 4 minutes. Remove from heat.
Add in vanilla and baking soda and stir mixture until it thick and glossy.
Pour half of caramel sauce over popcorn then toss several times, add remaining caramel sauce and toss popcorn until evenly coated.
Spread popcorn onto a cookie sheet and bake in pre-heated oven 1 hour, stirring popcorn every 15 minutes. Allow to cool completely.
Melt white chocolate chips and drizzle on top of popcorn.