We got our stove top popper quite a few years ago as a gift and love it so much that we have bought them for other people as gifts too.
I had to buy corn syrup for the recipe. The brand choice was obvious.
I followed this recipe, but took the advice in the comments to make a few alterations (including cutting the suggested butter in half!) and it turned out so good. I love online recipes that have feedback. Here is the recipe re-written with the modifications that worked perfectly for me. Yum.
1/2 cup butter
2 cups brown sugar
1/2 cup corn syrup
1 tsp. salt
1/2 tsp baking soda
1 tsp vanilla extract
5 quarts popped popcorn (about 5/6 cup kernels)
1. Preheat oven to 250 degrees F. Place popped popcorn in a large oven safe dish.
2. In a medium sauce pan over medium heat melt the butter. Stir in brown sugar, corn syrup, and salt. Bring to a boil, stirring constantly. Boil without stirring for 4 minutes. Place the popped popcorn in oven for the 4 minutes to warm it.
3. Remove from heat and stir in soda and vanilla. Transfer warmed popcorn to a very large mixing bowl. Pour caramel in a thin stream over popcorn, stirring to coat.
4. Place in two large shallow baking dished and bake in a preheated oven, stirring every 15 minutes for 45 minutes. Remove, let cool, break into pieces. Enjoy.