All That Jazz ▶
An exercise in chocolate decoration: These spectacular cakes are turned into miniature keyboards with jazz musicians made of chocolate decorating the plate and cakes. But the cake is delicious without the elaborate decorations — sponge cake layered with coffee buttercream, ganache, espresso, and Bailey’s Irish Cream, coated with chocolate glaze. Keep in mind that the amount of chocolate and oil needed to make the decorations will vary depending upon how many individual decorations you make, their size, and how elaborate they are.
- Jazz Musicians
- Vegetable Oil - 6 tablespoons
- Dark Chocolate - 20 ounces, chopped
- White Chocolate - 12 ounces, chopped
- Piano Keys
- Vegetable Oil - 2-1/4 cups
- Dark Chocolate - 1-1/2 pounds, chopped
- White Chocolate - 3-3/4 pounds, chopped
- Sponge Cake
- Eggs - 6
- Sugar - 1 cup
- Vanilla Extract - 1 teaspoon
- Almond Extract - 1 teaspoon
- Pinch of salt
- Cake flour - 1 cup, sifted
- Coffee Buttercream
- Water - 3 tablespoons
- Sugar - 1 cup
- Egg Yolks - 6 large
- Unsalted Butter - 2 cups (4 sticks), at room temperature, cut into pieces
- Coffee Extract - 2 tablespoons (alt. extra-strong espresso)
- Heavy (whipping) cream - 1-1/2 cups
- Semisweet Chocolate - 20 ounces, chopped
- Bailey’s Irish Cream liqueur - 1/2 cup
- Extra-Strong Espresso - 1/2 cup
- Chocolate Glaze
- Bittersweet Chocolate - 16 ounces, chopped
- Vegetable Oil - 1/3 cup
- Bittersweet Chocolate - 12 ounces, chopped
To make the musicians: Cut out small pictures of jazz musicians which you like; 4 to 5 inches in height work well. You will need to make a total of at least 8 decorations; you can use the same picture several times, or different pictures. Place the pictures on a baking sheet and cover with a sheet of clear plastic film like that used for overhead projectors. Make three small cones by folding 8-inch circles of parchment or other stiff paper and fasten the tops with paper clips; make a tiny snip at the points. Melt the chocolates separately in the top of a double boiler over barely simmering water; put them in separate bowls and keep warm, but not hot. Stir 4 tablespoons of vegetable oil into the dark chocolate; stir 2 tablespoons of oil into the white chocolate. Fill one cone with dark chocolate. On the plastic, outline the pictures with dark chocolate. Fill in areas you want to be dark with more dark chocolate. Set the cone aside. Fill another cone with white chocolate and add highlights to the pictures. Mix dark and light chocolates to create a tan color and finish filling in the pictures. Place the decorations in the freezer to set.
To make the piano keys: Line a baking sheet with clear plastic film. Melt the dark chocolate in the top of a double boiler over barely simmering water. Stir in 1/2 cup of the oil. With a spatula, spread one third of the dark chocolate into a rectangle about 2 inches wide, 15 inches long, and about 1/8 inch thick. Repeat with the white chocolate, adding the remaining oil. Spread one fourth of the white chocolate into a rectangle about 3 inches wide, at least 15 inches long, and about 1/4 inch thick. Put the pan in the refrigerator and chill until the chocolate is firm enough to handle, but not hard. Trim the edges straight. Cut across the dark rectangles at 1/2-inch intervals, making dark“piano keys.” Cut across the white rectangles at 1/2-inch intervals, making white“piano keys.” Cut all the way through to the plastic, separating the individual keys. Repeat two more times to make enough black keys; repeat 3 more times to make enough white keys. You will want at least 120 white keys and 80 black keys, plus a few extra to allow for breakage. Put in the freezer to set.
To make the cake: Preheat the oven to 350 F. Spray an 11-inch-by-15-inch jelly roll pan with vegetable oil spray and wipe out the excess. Line the bottom of the pan with parchment paper. Separate the eggs. In the large bowl of an electric mixer, beat the egg yolks just enough to break them up, then add 3/4 cup of the sugar and continue beating at medium-high speed until the mixture pales and thickens enough to form a ribbon when drizzled from a spoon back onto itself. Beat in the vanilla and almond extracts. In a deep bowl, beat the egg whites until just foamy. Add the salt and beat on high speed until soft peaks begin to form. Add the reserved 1/4 cup of sugar and beat until glossy, stiff peaks form.
Fold the flour into the yolk mixture in thirds. Fold a large spoonful of meringue into the yolk mixture to lighten it, then very gently fold in the remaining meringue. Pour the batter into the prepared pan. Bake 15 minutes, until the top springs back when touched and a toothpick inserted in the center comes out clean. Remove from the oven and cool completely. The cooled cake may be sealed in foil or a plastic freezer bag and frozen until ready to use.
To prepare the buttercream: In a small saucepan, combine the water and sugar and cook over medium heat until the syrup is registers 242 F on a candy thermometer (soft ball stage). Let cool slightly.
Place the egg yolks in the bowl of an electric mixer and begin to beat at high speed. Gradually add the sugar syrup and continue to beat until the mixture cools. Gradually add the butter, beating after each addition and stopping occasionally to scrape down the sides. Beat in the coffee extract or espresso.
To make the ganache: Warm the cream in a saucepan over medium heat. Remove from heat and add the chocolate; wait 30 seconds for the chocolate to soften, then begin stirring the chocolate and cream together with a spatula, working from the center outwards. Do not beat air into the mixture. Stir until smooth.
To assemble: Cover a sheet pan with parchment paper. Turn the cake out onto the parchment. Cut the cake in half lengthwise, then crosswise into thirds, making six 5-by-5-1/2-inch pieces. Split each piece in half horizontally through the center. You will have 12 very thin pieces of cake.
Dust off crumbs; trim any uneven edges. Brush four of the cakes liberally with espresso and Bailey’s Irish Cream; let it soak in. Spread these pieces with a thin layer of ganache. Spread them again with a layer of buttercream. Top each with another layer of cake. Brush the cakes liberally again with coffee and Bailey’s Irish Cream and coat with ganache, then buttercream. Repeat again, then top with a final layer of cake. Brush the top cake with Bailey’s Irish Cream. As you work, clear away any crumbs that occur. Chill in the refrigerator for at least 2 hours.
Make the glaze: Melt the dark chocolate in the top of a double boiler over barely simmering water. Remove from heat and stir in the oil. Take the cakes out of the refrigerator and cut each square in half on the diagonal. Set a wire rack in a baking sheet. Stand the triangles, points up, on the rack. Pour the chocolate glaze over the cakes to cover. Put the cakes back in the refrigerator for at least 2 hours.
To finish: Take the chocolate decorations out of the freezer and let warm slightly. Lift the decorations from the plastic backing. The chocolate may sweat a little from condensation as it warms; blot gently and let come to room temperature. Take the cakes out of the refrigerator.
Melt the 12 ounces of bittersweet chocolate in the top of a double boiler over barely simmering water. Put some of the chocolate in a paper cone (see above) and make a small pool of chocolate on a dessert plate. Anchor a cake, point up, in the chocolate. Draw a narrow line of chocolate across the lower end of the slanted surface of the cake and place a white piano key on the line; hold in place until it firms. Repeat, making a line of piano keys from the plate up the slanted surface. Use about 15 white keys per portion. Don’t try to be precise. Anchor dark piano keys over the white keys in the general pattern, 2 dark keys close together, space, 3 dark keys close together, space and repeat, with the melted chocolate, holding in place until they set. Pipe a little melted chocolate on the back of a jazz figure and anchor it to the cake. Figures may also be stood up in melted chocolate on the plate and held until the chocolate sets enough to hold them. Repeat with all of the cake pieces. Return to the refrigerator until ready to serve.
To serve: Just set this down and wait for the “Wow!”