Hola, Amigos! Stevia is a small green herb. It grows in South America,
Korea, and China, and probably other places, too.  There are stevia plants
for sale on the Net on some Herbal Webpages, should you care to look them
up. I will tell you what I know.
Stevia Rebaudiana (full name) is an herb that was first reported by Spanish
explorers in the 1700's. Indians ( don't know their tribal names)  in
Brazil and Paraguay  made a tea and used stevia to sweeten the tea.  Stevia
is 200-400 times sweeter than sugar. It can be purchased in Health Food
Stores in liquid or powdered form.  It comes in several "grades" - green
colored stevia is sort of a grade "c". You can buy this in a clear liquid
which equates to a grade "a". Green, especially powdered leaves a slightly
bitter after taste, the clear has no after taste.
It is used in Japan as the sweetener in "diet" Coke, etc. This sweet herb (
also known as "sweetleaf") has been attacked by the FDA and was banned for
sale in the US, after NutraSweet got wind of it, for 6 years.  It is for
sale now because there were no studies to back NutraSweet's claim that it
was "bad for you!"  There is documentation on the Net for those interested
- search using "stevia" and you will be inundated with information.
I have used stevia  for years but find I don't need it on Neaderthin.  If
you can find a use other than baking, more power to you!   Sherry