I've tasted something awful in pretty much every category (can't accuse me of not trying things
), but the worst had to be some nasty pu-erh. You who love pu-erh are amazing people!
A close 2nd was a Vanilla Carmel-something from Stash (in bags) I'd picked up at the grocery store a few years ago. At the time, it had to have been the worst thing I'd ever put in my mouth. So I emailed Stash, they sent a nice letter and coupons for a couple of free boxes of any Stash teas along with a half dozen bags of 2 other teas I already liked. Hard to beat that kind of customer service.
This morning so far I've enjoyed Adagio's TGY and now Ooooh Darjeeling.