Use a small container to cure your egg yolks. The smaller it is the smaller surface area the salt needs to cover before building up the sides of the container and over the yolks.
Fill the container with kosher salt to the depth of about an inch.
Separate your frozen egg yolk from the egg white and set it on top of the salt. Make sure the yolks aren’t touching so salt can fill the spaces in between.
Cover the yolks the rest of the way with more salt.
Set the container, uncovered, in the refrigerator for a week. They will be firm when they are done.
Remove the egg yolks from the salt and brush off as much as you can. You can use a moistened towel to help brush off some salt, but I didn’t bother getting it all off.
Wrap the egg yolks in cheesecloth and set them back into the refrigerator to finish drying out for another week. I set my cloth wrapped yolks in a colander.
You can cold smoke the egg yolks if you’d like. We used apple wood and smoked them for an hour.
Wait another day or so after smoking for the smoke to mellow out. Then grate or slice them to use wherever you’d like the flavor boost.
I put mine in a mason jar with a lid. They should be stored in the refrigerator indefinitely.