Make the chocolate dark (70% or greater cocoa content) and watch the portion size (20 g or so) and this is an amazingly healthful treat.
My prefrence is for raw almonds ... simply because I think they taste better.
I like Ghirardelli Intense Dark Chocolate 86% as it uses a "non-dutched" cocoa which preserves the flavanols that make dark chocolate so healthy. Also Lindt 85 and Green and Black's Organics 85 are non-dutched chocolate that you can find at Walmart and Targets for $3 or less.