What do you use for natural flavoring? Administrator August 16, 2017 19:11 Natural Vanilla Flavor, Natural Mandarin Orange Flavor, and Luo Han Guo. Related articles How can I be sure your "natural flavoring" is safe? Are any sweeteners besides Stevia approved for the Slenderiiz Program? Power Boost (Cocoa) How long do I leave the Slenderiix drops under my tongue and what do I do after? NuCerity Elite Comments 0 comments Please sign in to leave a comment.