Pop both bags of popcorn according to package directions. Empty popcorn into very large mixing bowl, remove un-popped kernels then set aside.
Heat butter, brown sugar, granulated sugar, corn syrup and salt in saucepan over medium heat. When mixture boils, set timer and continue boiling for 4½ minutes. Remove from heat; add vanilla and baking soda then stir to combine completely (mixture will bubble up).
Immediately pour caramel over popcorn and mix to coat popcorn evenly and add peanuts while caramel is still hot and sticky. Pour popcorn onto a baking sheet lined with wax paper, let cool.
Break into pieces and enjoy!
Notes
Break peanut butter cups and Heath bears into tiny pieces and add to this caramel corn for an extra decadent treat. Yum!