The Polish chocolatier Wawel produces a number of chocolate bars, this is the one with the highest cacao content I have seen, 90%. The ingredient listing is good, cocoa mass, fat reduced cocoa powder, sugar, cocoa butter, lecithin and E476 as emulsifiers, and flavours.
While not the highest cacao content I have seen, there are several at 90%, and Lindt sells one at 99%, I think most bars at this high cacao content suffer from being too chalky, that the lack of sugar is actually detrimental. Don't get me wrong, I eat raw cacao nibs, 100% cacao, but never straight, usually in a morning breakfast mixture, I just think bars taste better at around 70%. Not all bars do, but this one suffers from the chalkiness problem. Otherwise, it's decent chocolate. I don't think that I would buy this bar again.