Place sugar and egg yolk in a medium bowl; beat with a mixer at high speed for 3 minutes or until thick and pale. Beat in honey and butter. Add cocoa, 1/2 cup at a time, beating well after each addition. Stir in wine, water, orange rind, if desired, and wafers.
Spoon mixture onto a sheet of wax paper using a rubber spatula (mixture will be stiff). Using moist hands, shape mixture into a 6-inch log. Wrap log tightly with plastic wrap; chill at least 1 hour. Cut log into 1/2-inch-thick slices.