Burma Mike brought over 29 American chocolate bars, most dark.  Only two of the bars exceeded 80% cacao content, Theo's Ultimate Dark from Washington and the Ghirardelli Midnight Reverie from California.   I saved them for last.   Not because I saved the best for last.  After reviewing stackloads of bars on the Chocolate Republic, I've noticed that extreme dark bars, with greater than 80% cacao, are not my favorites.  I am a dark chocolate aficionado, but more in the semisweet range of 60-65%.     These bars got stuck in the refrigerator the longest because they were the exceptions.  The other bars were mostly 60-70% and could be compared amongst each other.   These two bars stood alone.    

Pulling off an acceptable ultra dark is tough.  With 80%+ cacao solids, you have less percentage left on the ingredient list to cram in much else.  Carrefour did a credible job with its 80%, and Green & Black's deserves kudos for their 85% organic. Many a manufacturer won't go above 70% because they know they don't have the chops.       

Theo's got the chops, all right, meeting the quality and taste set by the famous Green & Black's and also being organic and fair trade.   Keeping things pure, Theo has done as little as possible to modify their Dark 70% to Ultimate Dark 85%.  The calorie content remains the same, but the fat content has risen from 300 calories per bar to 340 calories in line with the higher cocoa butter content.  With more cacao, the fiber content rises from 8 grams per bar to 10 grams, but leaves less room for additional sugar, which drops from 24 grams per bar in the Dark to just 14 grams in the Ultimate Dark.  With such a pure cacao-for-sugar jump, you'd expect an equivalent jump in bitterness, but that never arrives. Theo's 85% performance is worthy of applause. 

85% is about the highest I'd typically go with a chocolate bar.  Lindt offers a 99% bar, but I consider it a gimmick. With 99% of the bar pure cacao, nearly everything comes down to where the cacao beans are sourced and hardly anything else to the expertise of the chocolate manufacturer.  Willie's out of the UK sells 100% cacao blocks, delicious in their own right.  These are not sold as snacking bars, but as cooking chocolate.  

Theo's been a studious child.  This 85% bar proves they're worthy of a diploma.