At Vienna’s esteemed Demel, those who want a sweet that isn’t too sweet might choose a slice of Burgtheatertorte. Bakers never let anything go to waste, even cake crumbs, and they are used here to make a moist chocolate-almond cake dotted with candied orange peel. The 4 cups of cake crumbs are easily obtained during a day’s work at a bakery, where the tops of countless cakes are routinely trimmed off, but home cooks will need a strategy (unless you are a frequent baker and freeze trimmings until you have reached the quota). You might bake a chocolate cake layer expressly for this recipe (the Chocolate Sponge Cake or Sachertorte batter on pages 8 or 59 are perfect), or buy an unfrosted cake at your favorite bakery. But remember, the better your crumbs, the better the cake.
1¾cups natural (with skin) sliced almonds
2tablespoonsDutch-processed cocoa powder
1cup plus 2tablespoons (2¼sticks) unsalted butter, at room temperature
6 large eggs, at room temperature, beaten
4cups (14ounces) chocolate cake crumbs, processed in a blender or food processor
Position a rack in the center of the oven and heat to 350°F. Butter the inside of a 9-inch springform pan. Line the bottom with a buttered round of wax paper. Dust the inside of the pan with flour, tapping out the excess.
In a food processor fitted with the metal blade, process the almonds, ¼cup of the confectioners’ sugar, and the cocoa until the almonds are very finely ground, almost a flour.
In a medium bowl, using an electric mixer on high speed, beat the butter until creamy, about 1 minute. Reduce the speed to low and add the remaining 1¾cups confectioners’ sugar. When combined, return the speed to high and beat until light in color and texture, about 2 minutes. Very slowly, beat in the eggs, then the cinnamon. Stir in the almond mixture, then the cake crumbs and the candied peel. Spread evenly in the pan.
Bake until a toothpick inserted in the center of the cake comes out clean, about 1 hour. Cool on a wire rack for 5 minutes. Run a knife around the inside of the pan to release the cake. Remove the sides of the pan. Invert the cake onto the rack, and remove the wax paper. Cool completely.
Turn the cake right side up. Using a long serrated knife, cut the cake in half horizontally. Spread the bottom layer with the warm glaze. Replace the top layer. Sift a generous layer of confectioners’ sugar over the top of the cake. Using a sharp knife, trace a crosshatch pattern in the sugar. Let stand at room temperature for 1 hour before serving.