Prepare Popcorn: Place popped popcorn into two shallow greased baking pans. If using peanuts, add them to the popcorn. Set aside.
Preheat Oven: Heat oven to 250°F (120°C).
Cook Caramel: In a saucepan, combine brown sugar, corn syrup, margarine, and salt. Bring to a boil over medium heat, stirring constantly. Once boiling, continue to cook for 5 minutes while stirring.
Finish Caramel: Remove from heat and stir in baking soda and vanilla. The mixture will foam up.
Coat Popcorn: Immediately pour caramel over the popcorn. Stir gently to coat as best as possible (it doesn’t need to be perfect yet).
Bake: Place pans in oven and bake for 1 hour, stirring every 15 minutes to evenly coat the popcorn.
Cool: Line a counter with waxed paper. Pour the caramel corn onto the paper, break apart, and allow to cool completely.
Store: Once cooled, store in airtight containers or resealable bags.
Serving and Storage Tips
