And it is very easy, which means no shaking of the pan or stirring mechanism is required.
I ate a lot of tough/chewy popcorn trying to find a combination that worked. I tried various things such as more/less heat, more/less oil, different types of oil, covering the pot with a colander so the steam can readily escape, different brands of kernels, shaking the pan, and so on, and what finally worked for me was about as simple as you can get: no shaking of the pan, and covered with an ordinary lid that is slightly ajar. The popcorn is now coming out as tender as I've ever had, it is popping to its full yield in approximately 3 minutes (4 quarts for 1/2 cup of kernels), and not a single burned piece, nor a single burn mark in the pan. Here are the details:
Pot: Saladmaster Tri-Clad 4 quart, manufactured in 1971. This pot has a raised center area on the bottom (here's a picture of it - http://imageshack.com/a/img268/6190/7...). The Whirley Pop pot also has a raised center area like that, so maybe that helps for making popcorn. The construction is 3-ply bonded metal: a carbon steel core sandwiched between two layers of 18-8 (304) stainless steel. Newer Saladmaster cookware uses an aluminum core instead of a carbon steel core.
Oil: The type of oil isn't really important in my experience, at least not with regard to how well it pops (it can make a difference in flavor, depending on how neutral the oil is). Based on how people online rave about coconut oil, I was expecting something amazing from it. Yes, it works great, but so does canola oil, corn oil (if you don't mind the taste it leaves behind), or clarified butter for that matter. I use a 2:1 kernel-to-oil ratio, i.e., 1/4 cup of oil to pop 1/2 cup of kernels.
Kernels: Orville Redenbacher's "Original" works best for me out of the small selection at my local store. And since I'm getting perfect results now, I don't see any reason to try anything else.
Heat: I have a plain old electric cooktop manufactured by Tappan (I wish I had a gas cooktop, but whatever). The heat setting is very important I have found, especially if you aren't shaking the pot. On my lower right large burner, 4.5 is the right setting (the knob is labeled 1 through 8). A setting of 5 will burn some of the flakes, as well as leave hard-to-remove burned residue on the bottom of the pot, and make the popcorn tough/chewy. A setting of 4 doesn't burn anything of course, but the popping is slow, the yield is down by about 25%, and again, the popcorn is tough/chewy. I heat the oil on 4.5 with a few kernels thrown in. When they pop, I dump in the 1/2 cup of kernels, give it a quick shake to evenly distribute the kernels on the bottom of the pan and coat them with oil, cover (with the lid slightly ajar), and stand back and wait.
After it is finished popping, I dump it into a paper bag, sprinkle on some Flavacol, shake it up, and it is as good or better than any I've had at the movie theater.