Signature Recipes

Chocolate Poco Sponge Cake
By Chef Zach Townsend

Yield: one 9 inch cake

1.3 oz / 38 g cake flour
1 oz / 28 g unsalted 80 percent butterfat butter, melted and kept warm
1/2 tsp vanilla extract
0.5 oz / 14 g unsweetened alkalized cocoa powder, sifted
1.4 oz / 40 g purified hot water
5.3 oz / 150 g whole eggs
3.5 oz / 100 g granulated sugar

Preheat the oven to 350 degrees F. Place the rack in the lower third of the oven. Prepare a half-sheet pan by lining it with parchment paper with overhang around the edges then spraying the parchment with baking spray that contains flour.

Sift the flour into a small bowl and set aside.

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Combine the warm melted butter and the vanilla extract. In a medium-sized bowl, combine the cocoa powder and hot water and stir well until smooth and no lumps remain. Cover and set aside to cool.

Place the eggs and sugar in a mixer bowl with the whisk attachment and whip on high speed for about 5 minutes or until the eggs are three times their original volume, thick and pale in color, and form a ribbon when drizzled.

Remove 1 cup of the egg foam and whisk it gently into the cooled cocoa mixture. Sift the flour over the remaining egg foam and fold gently with a whisk until no traces of the flour remain.

Pour the batter into the prepared sheet pan and gently spread it out evenly. Bake for 12 minutes or until the cake springs back when touched lightly in the middle.

Remove the cake from the oven and place it onto a large rack. Let cool about 5 minutes, then slide the cake in its parchment paper onto the rack and let it cool completely. Cover with plastic wrap and place in the refrigerator or freezer to firm up, about 1 hour. The plastic wrap will aid in removing the top crust when removed.

Coffee soaking syrup
4.4 oz / 125 g purified water
2.2 oz / 65 g granulated sugar
0.24 oz / 7g high-quality instant espresso powder

In a small saucepan, stir together the water, sugar and espresso powder. Bring to a boil. Immediately remove from the heat, cover and let cool. (The cake will need only 20g syrup.)

Poco mousse
8.9 oz / 255 g heavy cream, divided
6.3 oz / 180 g Cacao Barry Gianduja Plaisir (24% cacao) chocolate
0.63 oz / 18 g egg yolks
0.3 oz / 9 g granulated sugar, divided
0.88 oz / 25 g purified water
0.88 oz / 25 g hazelnuts, toasted and crushed into fine pieces

Add 6.3 oz / 180g heavy cream to a mixer bowl and refrigerate along with the whisk attachment.

Melt the chocolate over a double boiler. In a small bowl, whisk the yolk with half the sugar until light yellow in color. In a saucepan, bring the water and the remaining 2.6 oz / 75g heavy cream and the remaining sugar just to a boil.

While continuously whisking, slowly drizzle the hot cream mixture into the egg yolk mixture to temper it. Pour the entire mixture back into the sauce pan and stir over medium-low heat until it reaches nappe (becomes somewhat thick and forms a streak on the back of a wooden spoon when you drag your finger through it). Strain the mixture onto the melted chocolate and stir until smooth. While the chocolate mixture is cooling, whip the cream to medium-soft peaks.

When the chocolate mixture has cooled, fold in the whipped cream and then gently fold in the ground toasted hazelnuts.

Poco glaze
8 oz / 227 g Valrhona 55 percent cacao chocolate, chopped
8.2 oz / 232 g heavy cream
4 Tbs granulated sugar
4 Tbs purified water

Place the chocolate in a heat-proof bowl. Bring the heavy cream, sugar and water to full boil, stirring to dissolve the sugar. Pour the hot cream over the chocolate and wait 1 minute, then stir gently until the chocolate is completely melted and smooth. You will have more than is needed to coat the cake, but this will ensure an adequate quantity for good coverage. Any remaining glaze can be frozen for future use.

Assembly
When the Poco sponge cake is cool, cut two strips, one of approximately 8 ¾ inches x 2 3/8 inches for the bottom layer and the other 8 inch x 2 inch for the center layer.

Lightly spray the inside of an 18 inches long by 2 3/8 inches wide by 2 inches high U-shaped log mold and line it with plastic wrap, ensuring that there is extra left hanging over the edge of the long ends. Lightly spray the inside of the plastic wrap with non-stick spray. Place a piece of foil-covered cardboard that has been cut to the shape of the inside of the log mold and place it inside the mold at 9 inches from the end. The cake will be only 9 inches long and this cardboard piece will act as one of two ends of the mold. Place the Poco mousse inside a pastry bag fitted with a plain pastry tube and pipe the mousse into the plastic-lined mold. When half way full, place the 8 inches x 2 inches center cake strip on top of the mousse and press down gently to even it out.

Brush the 20g of coffee soaking syrup evenly all over cake layer. Pipe the remaining mousse into the mold until about 1/8 inch below the top edge of the mold and spread evenly. Place the second cake layer on top and press down gently to set. Cover the cake with the plastic wrap left hanging over the edge. Set in the refrigerator for several hours, preferably overnight, for the mousse to set.

When the mousse is set, remove the cardboard insert from the mold and unmold the cake gently onto a glazing rack by tugging on the ends of the plastic wrap. Keep the plastic over the cake and place it in the refrigerator to keep cool until the glaze is ready.

Gently bring the glaze to between 85-88 degrees F in a bowl or glass measure with a spout. Quickly pour the glaze over the cake to evenly coat it. Immediately place the cake in the refrigerator to stop the glaze from dripping and to ensure the cake is firm enough to move easily, about 5 to 10 minutes.

When the glaze is no longer dripping, take two large offset spatulas to lift the cake gently from the rack onto a serving tray.

Decor
2 whole hazelnuts, toasted
Gold leaf
One chocolate triangle, dusted with cocoa powder
25g (about ¼ cup) finely crushed hazelnuts, toasted

Place the two whole hazelnuts in the top center of the cake along with the chocolate triangle. Top the hazelnuts with gold leaf. Gently press the crushed hazelnut pieces into each end of the cake until well covered.

Zach Townsend is based in Dallas where he has operated Chocolate Desserts by Zach (www.purechocolatedessertsbyzach.com) since 2003. He also sells chocolate desserts at Paper & Chocolate in the Inwood Village in north Dallas.