Be sure to have all of your ingredient ready. Heat the oil in a 3-quart thick-bottomed saucepan on medium high heat. Add the popcorn and cover, let it pop, put them in another bowl and reserve.
Immediately, melt the butter in the same saucepan on medium high and add the sugar constantly mixing with a spatula, add the vanilla, let it boil until the caramel is a golden color. Bring out of the heat and add the popcorn, add the salt and stir well, let it cold and enjoy.