Put oil and a few popcorn kernels in a large pot- at least an 8 quart with a lid. (If you don't have a large enough stockpot, then just divide the oil and popcorn in half and pop it in two batches.)
Heat on medium high. When kernels begin popping, add the rest of the popcorn kernels and replace lid.
Shake gently using the handles of the pot. Popcorn will begin popping rapidly. (once you put all of the popcorn in the pot, it only takes a couple of minutes to be done.)
Listen closely, when pops space out to a few seconds between each one, the popcorn is done- remove it from the heat. Keep the lid on as a few more pieces will pop.
Transfer popcorn to a gigantic bowl or 2-3 smaller bowls.
Remove any unpopped kernels.