[header] How to make movie butter for your popcorn [title] Choose your salt. [step] Many movie theaters use salt processed using the alberger process, as the many jagged edges on the salt crystals help it stick to the popcorn. Diamond crystal is the only consumer salt brand in the united states that uses this process. 
You can get a similar effect from extra-fine powdered salt, which is often sold as " popcorn salt " and stocked next to the popcorn. [substeps] You can create powdered salt at home by grinding any salt in an electric coffee grinder, hand-turned salt mill, or mortar and pestle.