Notes: I organized a potluck at work recently, and offered prizes for the best dish in several categories. For my dessert entry, having an impressive appearance was one of my goals. This cookie has always been in the back of my mind ever since I bought the book. On the first day, I made the doughs and chilled them. On the next day, I let them come to room temperature, then shaped them. Do pay attention to the measurements so that everything fits together. I found it difficult to achieve the bread loaf shape. Every time I squashed from the top, the bottom would get smushed. Slice the dough very thinly, otherwise the finished cookie sandwich will be too thick. Another caveat: cutting the sandwiches on the bias causes the PB and J to ooze out everywhere. I tried to mitigate this in several ways: putting less filling before slicing, slicing then filling, and using a very sharp serrated blade, but none of these techniques solved the problem completely.
In the end, I was not the victor (a brownie won). But I think these cookies are very fun, and certainly were impressive to look at.
Here's Ipso Fatto's rendition.