A compromise for long term storage and the fact that chocolate can melt: chocolate brownie mix in #10 cans or chocolate chip muffin mix. You get the chocolate kick with something that lasts years. Medium range scenario, you’re eating it after getting laid off or when you rotate your food stores.
Excellent idea. Also, cocoa powder lasts forever. Chocolate syrup in a can will also last a long time. I found some in a can a year ago but don't know if they still make it. With the bottles being plastic and not sealed as well, those probably won't last as long. Here's a recipe for home canning chocolate syrup:
http://threeboysandglutenfree.blogspot.com/2010/11/canned-chocolate-syrup.html