The inspiration for this post comes entirely from Food in Jars and their post on Meyer Lemon Zest Sugar and Salt. I had a couple meyer lemons lying around that I wasn't sure what I wanted to do with, so one gave its zest to become infused salt.
Infusing salt is a pretty simple process, as are many infusions. You mix what you want to infuse into what you want infused, and if they are compatible, then infusion usually happens on its own. We infused vanilla into sugar and vanilla into alcohol, but I figure it's time to give the many, many vanilla beans I still have left a rest and go for something different.
For this you need salt (I used kosher, but strictly speaking whatever you want to use will work), something with essential oils that you want to infuse into your salt, and a method of making that infusing substance small. For infusing, options are herbs, citrus fruits, truffles, or anything that smells good and doesn't contain a lot of water. You're going for the oils here, not water, which would cause you trouble by making the salt dissolve or stick together.
For the lemon, I zested it with the microplane, as is my wont.
The nice things about the microplane are that it's easy to use and the zest is in such a handy form for just about anything.
Next you layer the salt with the zest.
Once you have enough lemon salt for your purposes, you seal the jar. I used my traditional "plastic wrap and jar top" method that you have seen many times before on the site.
That's it. This salt will be particularly good with fish, but you could also use it to top the shortbread cookies for a bit of lemon flavor, or as an addition to anything you want to be lemony.