I made this a few weeks back and just transferred to keg last night. I soaked the nibs in vodka for a week or so before secondary, and I also soaked the vanilla beans in bourbon (after slicing them open to reveal the goodness inside). I used S-04 yeast instead of the kolsch, but I followed the rest of the recipe. I got to taste a little when transferring to the keg and it was delicious. About two more weeks of waiting before I tap it.