Croissants – but they disappointed me: they never have the crisp lightness of the originals. After a while I began to wonder if they were made with animal fat instead of butter; a bit heavy, and over-sweetened too. Then recently, when I asked reluctantly for a media luna to go with a coffee I was asked if I wanted a 'media luna de manteca' – a butter croissant! I tried asking for a media luna de manteca at another cafe and was told they had only 'media lunas de grasse' – fat. So it seems you can choose between media lunas made with butter, or with fat. Take your pick.
I've never seen this mentioned anywhere. Media lunas de manteca still hardly resemble French croissants, but I find them more digestible and less sugary.