Come to think of it, I used to work in a chocolate store. (Somehow I was a size 4 then...)
Anyway, we made truffles like that, layered ones. Each layer was poured on top of the other onto a tray lined with parchment. After they set, we just flipped the tray over, cut into 1 inch squares and used a fork and spoon to dip them in regular chocolate. They sold even better than the round pre-made truffles from the main factory.
MMMM I think I have to go visit the girls at the old shop again soon!!