Wonderful recipe! I didn't add the optional espresso powder as I felt it would be too strong for my taste. also the type of baking chocolate was not specified...there is more than one kind, I went with the normal unsweetened and it turned out amazing! also...after cooling for a while in fridge I scooped out approximately the amount for each ball and let them cool in fridge on baking sheet...then took it out a bit later to shape them more. This seemed to work better since otherwise you would need to let them cool for several hours.