Preheat your oven to 350 and spray a pan with non-stick spray or line it with parchment paper.
To prepare, in a separate, small bowl, have your finely chopped walnuts ready to roll your cookies in.
In a medium sized mixing bowl, combine your coconut oil, almond butter, and honey. Whisk till smooth.
Add your vanilla and only your egg YOLK. Put your egg WHITE into another small bowl, for rolling your cookies in. Whisk again till all is well combined.
Add in your flour and salt, and stir till your dough is formed.
Using a cookie scoop, scoop out about 15 cookies onto a plate.
Whisk your egg white till its fluffy and bubbles begin to form (about a minute or two).
Now, dip each cookie into the egg white, rolling it around so its covered completely, and then dip it into your chopped nuts, rolling it around again so its covered completely.
Dip and roll each cookie and place them on your pan, a couple inches apart (these cookies don't spread).
Using your thumb (or 1/2 teaspoon measure), lightly push down and form a small indent in the top of each cookie as the "thumbprint." Your thumbprint will hold about 1/2 teaspoon of jelly. If one side of your cookie cracks, gently push it back into place.
Once all your cookies have been thumb-printed, add 1/2 tsp of jelly into each thumbprint hole.
Bake in the oven for about 8-10 minutes, or till the edges of the cookie are starting to just turn golden brown.
Let cool and devour!
*Store in an airtight container for a week or so.