In a small pot, melt coconut oil over low heat. Remove from heat and stir in carob powder, sweetener and vanilla extract. With a whisk, combine until smooth. Place on a small square or rectangle metal, glass or ceramic tray. Refrigerate for 30 minutes or more or until solid. Remove from refrigerator and with a sharp knife, cut lines vertically and horizontally making small square chips. Keep in the refrigerator.