In a large saucepan, heat the vegetable oil with 3 popcorn kernels over medium-high heat until shimmering.
Keep an eye out for the kernels to pop; as soon as they do, the oil is ready (remove the three popcorns quickly so they don't burn).
Put the remaining popcorn kernels in the saucepan and cover it.
Shake the saucepan to ensure that the kernels are all in one layer.
Keep cooking the popcorn with the lid on over medium-high heat until all of the kernels start popping.
Gently shake the pan from side to side and back and forth a few times.
The popcorn is ready when the popping has slowed to one pop every few seconds.
In the meantime, take a pan and put some foil on it and spray it with cooking spray.
Take the cover from the popcorn and place it in the saucepan.
To the prepared popcorn, add the pecan halves.
In a separate pan, over medium heat, melt the butter.
Add brown sugar and corn syrup and cook for 5 minutes, stirring continuously.
After 5 minutes add baking soda and vanilla extract and mix very well with a spoon.
Pour the sauce on top of the popcorn and pecans and toss them with a spoon.
Bake the popcorn in a preheated oven at 250 degrees Fahrenheit for 1 1/2 hours.
Remove the pan from the oven and break the popcorn.
Enjoy Brenda Gantt Caramel Popcorn!