Melt the Chocolate: Pour the dark chocolate melting wafers into a microwave-safe bowl, and microwave on high for 30 seconds, 3 times, stirring in between.
Prepare the cake roll: Place the cake on a cardboard cake round surface and then optionally, on top of a rotating cake stand. Cut 1/4 of the end of the cake roll.
Cover the cake roll: Using an offset spatula, cover the cake roll evenly in the melted chocolate. If it gets hard, then you can always put the chocolate in the microwave to get it melted again.