These are truly incredible. I added 3/4 tsp of chipotle powder for some heat, and used toasted pecans instead of walnuts. I also love someone else's suggestion of adding crushed peppermint candies. Yum!
I'd like to note that I used 4 oz. of dark chocolate chips, and the boiling water didn't melt them all the way so I ended up having to place the bowl with the chocolate paste into the preheating oven. I think this caused the paste to burn ever-so-slightly, but thankfully it wasn't evident in the finished product. If I end up using chocolate chips the next time I make this, I'll probably melt them on the stove with the vegan butter over low heat, and sift the cocoa powder with the flour instead of adding it to the melted chocolate. Hopefully that won't mess with the end result.
This is a recipe I will continue to play with since it is a winner!