In your large pot, add the coconut oil and place it over medium heat. Allow the oil to melt, which should take about a minute.
Once the oil is melted, add the popcorn kernels to the pot. Make sure they are spread evenly across the bottom of the pot.
Cover the pot with the lid, leaving it slightly ajar to allow steam to escape. You will start to hear the kernels popping within a few minutes.
As the popcorn begins to pop, gently shake the pot occasionally to prevent burning and ensure even popping. This should continue for about 3-5 minutes.
When the popping slows down to about 2 seconds between pops, remove the pot from the heat. Immediately add the granulated sugar and sea salt. Stir quickly to coat the popcorn evenly.
Pour the kettle corn into a large bowl and let it cool for a few minutes before enjoying. This allows the sugar to set and helps the popcorn stay crisp.