Using a large pot with lid, put the popcorn in the cold pot. Tilt pot so all the popcorn piles up on one side. Pour oil directly on the popcorn.
Tilt the pot in all directions to coat all the cold popcorn kernels with the oil. Tip: if popcorn kernels go skipping across the bottom of the pot when you tilt it, they are not covered in oil yet. When all the kernels slide slowly across the bottom of the pot, they are ready to cook. Make sure all the kernels are in a single layer on the bottom of the pot.
Cover pot with lid. Turn on heat to medium-high. Wait until you hear 1st pop. Then turn heat to medium. Do not walk away.
Wait for popping to slow. Remove from heat.
Add salt. Cover the pan and shake to distribute salt.
Divide into bowls. Taste for salt, adding more as desired.
Notes
For buttered popcorn that’s not soggy, use about ¼ cup clarified butter (more or less to taste). How much water is in the butter will vary by brand – some have more and some have less. Start with ½ cup of butter to make sure you get ¼ cup.To clarify butter in the microwave:
Place butter in a microwave safe 4 cup Pyrex measuring cup, and microwave on high for 1-2 minutes. Do not stir. Let sit for a few seconds.
Check the butter. If the butter is completely melted and there’s a yellow clear layer on top with a lighter opaque layer on bottom, it's clarified. If the butter is still a bit cloudy, microwave for an additional 1 minute until separated.
Spoon just the top clarified butter into a separate dish for use.
To clarify on the Stove top:
Place the butter in a small pan, and bring to a boil over medium heat. White foam will build up on the top of the melted butter.
Remove the pan from heat and scrape the foam off with a spoon.
Put the pan back on the medium heat, but be careful not to burn it. Remove any more foam that develops.
Drizzle the clarified or melted butter on the popcorn, giving the bowl a toss and continue drizzling as you toss. Add the salt as you toss and it should stick to the butter nicely.