I have yet to come across such a unique concept for a shop/cafe in the area.
Not only is the Chocolate Lover's Club a chocolate shop, it's also open for dinner on Thursday and Friday nights. The owner tries to incorporate chocolate or cocoa into savory dishes. I've only had the chili there, but I've heard the mole is authentic and delicious. I plan on attending the monthly "supper club" which is a dinner revolving around a specific country's cuisine (Mexico, Hawaii, Brazil, etc). And of course, ending the night with some chocolate dessert.
I recommend giving it a try. Even if you just go to pick up some chocolate for the holidays. I recommend the chocolate covered oreos or the chocolate turtles (they are my favorite): http://chocolateloversprinceton.com
Chocolate Lovers Club
Stanhope St, Plainsboro, NJ 08540