1. In a large pot, heat the oil over medium-high heat. Add three popcorn kernels; when these pop, add the remaining kernels and cover the pot. Pop the corn, shaking the pot frequently, until you no longer hear popping, about 5 minutes. Uncover, remove from the heat and set the pot aside.

2. In a large, heavy pot, melt the butter over medium-high heat. Add the sugar and corn syrup and bring to a boil, stirring constantly. Once the sugar boils, stop stirring and insert a candy thermometer. Continue cooking until the mixture reaches 280º, then cook for 30 seconds longer or until slightly darkened. Remove the pot from the heat and very carefully stir in the salt, baking soda, vanilla, peanuts and popcorn.

3. Use two heat-resistant spatulas or wooden spoons to carefully spread the caramel corn out on a silicone-mat- or parchment-lined baking sheet. Let cool for 1 hour, then break into pieces. Store in an airtight container for up to one week.