I can't take credit for either of these recipes, but I can take credit for combining the two!
Michael Smith's Chocolate Chip Biscotti as well as his Dark Chocolate Paté
See above for recipe method link
I didn't refrigerate the pate and it remained soft and perfect for dipping.
Once chilled it sets into a paste which can then be spread onto the biscotti.
Although Michael's recipe says to leave the biscotti until cool enough to handle, I would say that (given my experience with the recipe) it would be best to allow it to cool completely. The outer edges were cooled, and they sliced quite neatly. But towards the centre of the log, where heat was still trapped, it crumbled and broke. It wasn't a great drama - they were still edible, just didn't look quite as nice as the 'end' bits which cut cleanly.