I've also read that a vanilla bean with the chocolate is a good idea. I've never done it. What I have done is close, I suppose. I do 4 oz. of cocoa nibs soaked in VANILLA VODKA for a day or two prior to adding the entire mixture (nibs + vodka) to secondary. Use enough vodka to cover the nibs. The next day the nibs will be all kind of gooey and stuff 'cause the nibs soak up the vodka so while initially there will be vodka on top of the nibs, by the time you rack all that liquid will be in the nibs themselves. Dump that gooey goodness in your secondary and wait 2 weeks. I just bottled NB's chocolate milk stout last night doing this and it was my best sample ever. I really enjoy flat, warm beer - that's all I needed to know!