Preheat oven to 220 degrees.
Combine salt, lemon zest and thyme in the mortar and then grind with the pestle. Really get in there so you can make sure that everything is well ground.
Add the salt to a baking sheet lined with parchment paper and bake for one hour.
When done, grind the salt again with the mortar and pestle if you prefer to have a finer salt.
Store and enjoy! Use on chicken, fish or pork.