Air-pop your popcorn and transfer it to a very large heatproof bowl, removing any unpopped kernels.
Preheat the oven to 250°F and line the baking sheet with parchment paper.
Bring coconut oil, brown sugar, and agave nectar to a boil in a small saucepan on the stove for 3–5 minutes, stirring constantly.
Then remove from heat and quickly whisk in the baking soda, vanilla, and remaining spices.
Working quickly, pour the hot glaze over the reserved popcorn in the large bowl. Use a spatula to fold and toss until most pieces are gently coated.
Spread popcorn on a large parchment-lined rimmed baking sheet.
Bake at 250°F (120°C) for 45 minutes, stirring gently every 15 minutes to redistribute the caramel and prevent burning.
Remove from the oven and let cool completely on the sheet; once cool, store in an airtight container in a cool, dry space.