To make a classic crunchy caramel corn, place popcorn in a preheated oven, make caramel, pour the syrup over the popcorn and bake for 45 minutes. This recipe takes about an hour to cook.
Preheat the oven to 250 degrees Fahrenheit and spray cooking spray on a large shallow roasting pan. Add 4 quarts popped popcorn before placing in the oven.
Next, mix 1/2 cup corn syrup, 1 cup brown sugar, 1/2 teaspoon salt and 1/2 cup butter or margarine in a 2-quart saucepan. Bring the mixture to a boil while stirring constantly. Allow the mixture to boil for 5 minutes without stirring.
Remove the mixture from the heat and thoroughly stir in 1 teaspoon vanilla extract and 1/2 teaspoon baking soda. Remove the popcorn from the oven and pour the syrup over the popcorn while it is hot. Stir to coat the popcorn evenly.
Return the popcorn to the oven and bake for 45 minutes while stirring occasionally. Spray cooking spray on foil paper, remove the popcorn from the oven and spread it on the foil.
Allow the popcorn to cool before breaking apart. Store the caramel corn in a tightly covered container to keep it fresh and crunchy.