Preheat the oven to 250 degrees F.
Spray a sheet pan with nonstick spray and line with parchment paper. Spray the parchment paper with nonstick spray as well and set aside.
Combine the popcorn and peanuts in a large mixing bowl. Set aside until ready to use.
Pour the syrup over the popcorn and stir to combine. You will need to work quickly because the syrup hardens rapidly. Spread the mixture onto the prepared sheet pan and bake in the oven for 1 hour. Cool completely.
Break into pieces and serve immediately or store in an airtight container for 2 to 3 days.
Recipe courtesy Alton Brown, 2006