No clue how this one is going to turn out. After some research on the internets there's a whole other set of walnut liqueurs that uses them still with shell (when green). These are just some walnuts from our farmer's market. No clue how it will turn out.
Recipe I used (based on different sources, included pictured book):
3 cups vodka
8 oz walnuts
30 currants
cinnamon stick
3 cloves
I'm going to let it steep in a cupboard for a couple of weeks and see how it goes.
NOTE: Had 6 cloves in for the first day. Smelled it after 24 hours and took 3 out.