Preheat your oven to 180℃ and gather your ingredients! (Place half a cup of erythritol into a blender and blend for a few second if needed. You should end up with a fine, powdered sweetener!)
Combine the peanut butter, powdered sweetener and the egg and mix very well.
Roll the cookie dough into 1-inch balls and place on a parchment paper lined baking sheet. Press down with a fork twice to create the iconic peanut butter cookie pattern.
Bake in the oven for about 10-15 minutes or until you see the cookie edges turn a darker brown.
Let them cool on a wire rack and enjoy with a yummy glass of nut milk!