Grab a medium bowl and whisk together the almond flour, erythritol, baking soda, and salt.
In a separate bowl, whisk the egg, melted butter, and vanilla extract.
Pour the wet mixture into the dry ingredients. Stir until you get a thick, cohesive dough.
Use a small cookie scoop or tablespoon to portion the dough onto your prepared baking sheet.
Bake for 10–12 minutes. Watch carefully toward the end. They should be set around the edges but still soft in the center.
Let them rest on the baking sheet for a few minutes before transferring them to a cooling rack.