Blend all dry ingredients together in a small mixing bowl, set aside.
Mix melted butter, xylitol and vanilla at medium speed with an electric mixer until well blended. Add eggs one at a time, mixing well after each addition. Gradually add dry ingredient mixture, beating until blended. Gently mix in cocoa nibs with a wooden spoon or spatula.
Spoon rounded teaspoonfuls of cookie dough onto a cookie sheet coated with non-stick vegetable oil spray. Gently flatten cookies by pressing with hand or spatula.
Cook at 375° F for 10 to 12 minutes or until done or until lightly browned. Remove from baking sheet and place cookies on a wire rack to cool. (Do not overbake cookies or they will be dry and hard.)