Preheat oven to 250F
Melt buter on medium heat
Stir in brown sugar, corn syrup, salt.
Bring to a boil while constantly stirring.
Boil without stirring for 4 minutes.
Remove from heat, stir in vanilla and baking soda.* * * WARNING * * * The caramel will foam up a lot when you add liquid to it, so make sure your pot is at least 3 times taller than the height of the caramel sauce before you add the vanilla. Pour caramel in a thin stream over the popcorn while stirring, and keep stirring until evenly coated.
Place popcorn in a large shallow baking dish, heat for 1 hour, stirring every 15 minutes.
Remove from oven and “let cool completely” before inhaling, er breaking into pieces.
Optional – add 1/2-1 cuppa crushed peanuts to the caramel mix. Don’t worry if the peanuts fall off – those little bits of peanut&caramel goodness will end up somewhere tasty.