Adapted from My Amish Friends Caramel Corn Recipe
Makes 28 cups

7 quarts plain popped popcorn(I prefer air popped)
2 cups dry roasted peanuts (optional)
2 cups brown sugar
1/2 cup light corn syrup
1 teaspoon salt
1 cup unsalted butter, cut into small pieces
1/2 teaspoon baking soda
1 teaspoon vanilla extract

Place the popped popcorn into two greased baking pans. You may use roasting pans, jelly roll pans, disposable roasting pans. (I find a 9x11 glass pan works the best to stir the popcorn in when baking). Add the peanuts to the popped corn if using. Set aside.

Preheat the oven to 250 degrees F. Combine the brown sugar, corn syrup, butter and salt in a saucepan. Bring to a boil over medium heat, stirring enough to blend. Once the mixture begins to boil, boil for 4-5 minutes while stirring constantly or if using a candy thermometer, when the thermometer reads 250 degrees.

Working quickly, remove from heat, and stir in the baking soda and vanilla. The mixture will be light and foamy. Immediately pour over the popcorn in the pans, and stir to coat. Don't worry too much at this point about getting all of the popcorn coated.

Bake for 1 hour, removing every 15 minutes to give the popcorn a good stir. Line the counter top with waxed paper. Dump the corn out onto the waxed paper and separate the pieces.
Allow to cool completely, then store in airtight containers or resealable bags. I love the look of caramel corn filled glass mason jars, great gift idea.

Note: This recipe will lightly coat all the popcorn pieces if you like a heavy coating use 6 quarts of popcorn instead of 7.