a kitchen paintbrush; a piping bag fitted with a large star tip
Cut a piece of parchment paper to 6 by 15 inches. Spread the chocolate on the center of the parchment to 1/8-inch thickness using a large offset spatula. Roll up the parchment from a short end and place in the refrigerator until firm, 20 to 30 minutes.
Unroll the chocolate on a work surface. Place the curved chocolate pieces upright around the sides of the cake. Lightly dust the chocolate pieces with luster dust using a kitchen paintbrush. Spread the pie filling on top of the cake. Transfer the whipped cream to a piping bag fitted with a large star tip. Pipe swirls of whipped cream on top of the cake. Garnish with the maraschino cherries.