Because we have no microwave (yes, you can make popcorn at home without microwave - I thought everyone knew that but apparently not, judging by the incredulous look I got from my housemate).
You need popcorn kernels, sugar (I used raw sugar but white or brown is fine), cooking oil, and salt. And a semi-huge pot with a sturdy lid. The lighter the better. And mittens or pot holders or anything to protect your hands.
I used this brand because it's the only one I could find. Bonus points for the resealable bag.
So first you heat enough oil to coat the pot. First drop three kernels, put the lid on, and wait for them to pop. Doing this makes sure you get the right temperature. Otherwise you may end up with chewy popcorn. Not good.
After the three kernels have popped, put in enough kernels to cover the entire surface area of the pan with one layer, and add in a couple of tablespoons of sugar. Mix it all in, put the lid on, and start shaking. When the popping has slowed down to maybe once every two seconds (or if the pot is already full), turn off the heat. Wait for the popping to stop entirely, dust the popcorn with salt, and hello kettle corn.
Of course if you owned a microwave, all you need is two minutes on HIGH, but where's the fun in that?
P.S. I also tried to add cayenne pepper one time, and it's strangely yummy in a really weird way. But then again, I like cayenne pepper on everything.