Don't make this unless you plan on eating a whole bag of puffcorn in one sitting. It's deliciously addictive. A perfect snack day or night. A sweet and salty bite. Double the recipe if you want enough to share, it disappears right before your eyes.
Preheat the oven to 250 degrees F.
Pour the popcorn in an oven safe pan or cookie sheet.
In a medium pan, mix together the butter, sugar, corn syrup and salt. Bring to a slow boil and boil for five minutes without stirring.
Once it's boiled for five minutes, remove immediately and add the baking soda and vanilla and stir together. Pour this over the popcorn and mix.
Bake for one hour. Stirring every 15 minutes.