If possible, grind up the sugar in a highspeed blender or spice grinder if using a type that comes in larger flakes/chunks, like most organic kinds do.
Mix sugar with the salt and candy caps, then add the almond meal and egg, then stir for a minute or two until a soft dough forms.
Roll the dough into 1 inch log, wrap in wax paper or plastic wrap and chill overnight, or for at least 30 minutes.
To bake the cookies, preheat the oven to 325. Slice the cookies into roughly ¼ inch thick rounds, lay onto a baking sheet lined with a silicone mat or other non-stick surface, like cast iron.
Press each cookie with the back of a butter knife or off-set spatula to form a cross, then bake for 20 minutes, or until just lightly browned *. If you cook them golden brown like regular cookies they can become crisp instead of keeping a chewy center.
Remove the cookies from the oven to cool. You want the cookies to be slightly underdone and chewy. Finished cookies will keep for a week, and can be stored in a cookie tin at room temperature.
Notes
*When in doubt, remove the cookies a bit early, or leave them in the oven with the door cracked open—for eating as-is, they’re good if they’re a bit underdone and soft on the inside. If you want to bake with the cookies as an ingredient as is done in Italy, preheat the oven to 350 and cook them until cracker dry (20-25 minutes) for grating over squash ravioli, adding to custards before baking, or another purpose.