In a mixing bowl fitted with the paddle attachment, or by hand, mix together the cake scraps, cocoa powder, powdered sugar, vanilla and nuts.
Stir in the 2 tablespoons of honey and the rum. Using your hands, try to form the mixture into a ball. If the mixture won't hold together, add a little more honey.
Roll the mixture into 1-inch balls, then roll them in powdered sugar. Let them sit for about 24 hours.