Preheat the oven to 200°F (93°C). Line two large baking sheets with parchment paper and set aside.

In a large bowl toss together the popcorn and peanuts. Set aside.

Combine the sugar, corn syrup, butter, and salt in a heavy duty saucepan over a medium-high heat. Stir constantly with a wooden spoon until butter is fully melted. Once butter is melted, increase heat and bring caramel mixture to a full boil. Boil for 5 minutes, stirring occasionally. Remove caramel mixture from the heat and quickly stir in the baking soda (this will cause the caramel to foam and bubble up). Stir in cayenne pepper and pour caramel over the popcorn. Stir gently, until all of the popcorn is coated.

Pour caramel coated popcorn onto prepared baking sheets and bake at 200 degrees F for 1 hour, stirring popcorn every 20 minutes. Allow caramel corn to cool completely on baking sheets, then break apart into large clusters.