DIY Popcorn Salt
How to make your own popcorn salt in a food processor
Place 1 cup of kosher salt into the bowl of a food processor
Put the lid on.
Run the food processor 30 seconds. Then hit the pulse buttons 5 times. Repeat until salt is very fine.
Wait a minute before opening the lid.
Add to a jar with a few kernels of popcorn to help prevent clumping.
You can also use a coffee grinder. Make sure it's very clean first, then grind the salt in it until a fine powder.