I got into fermenting herbal tea a couple years ago. This is the tea leaves I use. Has a tiny bit of caffeine with a tad of sweet and the kick of a mule if you let it go for a month.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
It's easy and cheap, and a cool little side hobby and tastes unique and awesome.
Just call me 'tangent'.