NOTE: You can use a thermometer to get the mixture to the right temperature, but I never used one in college and I usually don't use one now for this recipe. The mixture will just get to a point where it is thicker and starts to get a tiny bit darker and that's when it is ready. Since this isn't candy, you don't have to be quite as exact with the temperature but you definitely don't want to undercook since you will have soggy popcorn and you don't want to overcook or it will be too hard.