In a large pot, heat the coconut oil and 3 corn kernels (and salt, if using) over medium-low heat, pot lid on.
Once you hear the 3 corn kernels pop, remove the pot from the heat.
Add the remaining corn kernels, replace the lid, and count 30 seconds.
Put the pot back on medium heat and set the lid slightly off the pot, but not much...just enough to let some steam escape.
Corn kernels will start popping rapidly. Shake the pot back and forth occasionally.
Once popping slows down dramatically or stops, remove the pot from the heat, leaving the lid on for a few seconds more to contain any straggling popping kernels.
Pour popcorn into a bowl. Add the butter or ghee to the hot pot to melt. Drizzle over popcorn. Then add all the popcorn back to the pot to soak up any remaining butter and salt.