This is a guess, but maybe butyric acid produced by anerobic bacteria? Butyric acid is ‘buttery and unpleasant’ vs Diacetyl which is a lot of the smell in good butter, and should be in Cheddar (and many other cheeses).
Not Balkan specific but ‘The Cooking of the Eastern Mediterranean’ by Paula Wolfert is great. It’s older though so it isn’t Instagram worthy photos, just great recipes, and commentary about how things are done. Like baking/ cooking in large Tandoor in Georgia.
There is also ‘Croatia at Table’ by Ivanka Bilus. This does have the photos and explains about different regions, things like butter/ cream in the north, olive oil in the south etc. The recipes are fine, but no standouts to me at least.
It said that Google put it in their aggregated report. Not that they disclosed it. There is a big difference between ‘we got 100 requests’ and ‘we got 10 requests for X info, 30 for Y info’.
ETA: I just looked at the data again, it’s broken in to categories like FISA NSL etc, then it just gives a range of requests 0-1000 etc.
For cakes I like using leaves brushed with chocolate.
Wash some green leaves (preferably something non toxic), dry, chill in fridge, brush with melted chocolate, chill again, peel the leaf from the chocolate.