In a moment of ridiculousness I promised my fella a birthday cake that involves 3 lbs of chocolate. Obviously decoration takes care of some of it- I'm thinking of rings of truffles on top, or hershey's kisses if I'm running short on time. And ganache is a no-brainer. But I'm having trouble figuring out how to incorporate a significant amount of chocolate into the cake itself, since most recipes use a fairly small amount. Suggestions?