Best Seller Caramel Corn

When I make this recipe, it's the only time I haul out my hot-air popcorn popper; use 1/3 cup popcorn to achieve the 8 cups of popped corn.
Preheat oven to 275F; have ready a jelly roll pan.
Place popped corn in a very large bowl.
In a large, heavy saucepan over high heat, combine the sugar, butter and corn syrup and bring to a boil; let boil for two minutes, stirring continuously.
Remove from heat.
Note that it is IMPORTANT to use a large saucepan, as this mixture will bubble up.
Add baking soda and vanilla to sugar mixture and combine well.
Pour this mixture over popped corn and combine, then spread mixture out onto jelly roll pan.
Bake in preheated oven for 40 minutes, stirring well every 10 minutes.
Let cool before eating.