What is this fungus/lichen in my Garam Masala? (“Trifle”/truffle?)
It seems to be an edible lichen.  It looks very like one described online as (black) stone flower in English and dagad phool in Hindi, which seems to be a not uncommon ingredient in various spice mixes; e.g. on the left in this photo from an Indian food blog:

[Edit: photo removed as I’ve just realised the author of that blog specifically requests not redistributing their content.  It’s a nice photo + site, though, if you follow the link!]

Having found these names, it’s now not hard to find a lot of websites mentioning it, especially in blogs/forum threads; but I can’t find any site in English that gives much detailed information.  Even its purpose in the mix is a bit unclear: some blog commenters describe it as having a unique earthy, mushroom-y flavour; others, as being similar to star anise; Wikipedia even seems to suggest it might just be a bulking agent.  (I don’t get any particular scent off it, at least not dry.)

So I think this is probably the right identification; and I’m reassured that it’s not something wrong with the mix; but I’m still quite intrigued, and would love to hear more about this ingredient from someone who knows it better!