Wash and chop 2-3 large stalks of celery. You can always do more (I’ve done the entire bunch), just depends on how much you want to make. Transfer to a baking sheet lined with paper towels and pat dry. Let it sit overnight to help get rid of some of the water, otherwise it will take 8+ hours of oven time. 

The following day, preheat the oven to the lowest possible setting (mine gets down to about 175°F/80°C). Place celery on a parchment or silicone lined baking sheet and place in the oven. Cook for 5-6 hours, until the celery is dry enough to crunchin your hand. It will shrink down significantly. Let celery cool completely before moving into the next step.

To make celery salt: Combine equal parts dehydrated celery to salt (1/4 cup celery + 1/4 cup salt, 1 cup celery + 1 cup salt, etc) in a high speed blender or spice grinder and pulse until there are no large chunks remaining. Store in a lidded jar.