This cake, which combines a luxurious white chocolate mousse with espresso soaked chocolate sponge cake, comes from the wonderful new book The Italian Bakery: Step-by-Step Recipes with the Silver Spoon (Phaidon, 2021) by The Silver Spoon Kitchen.
- ½ cup (50 grams) unsweetened cocoa powder
- Scant ½ cup (100 ml) whole (full-fat) milk
- Scant ½ cup (100 ml) freshly brewed espresso coffee
- 6 large eggs
- ⅔ cup (120 grams) superfine granulated sugar
- 1 teaspoon vanilla paste or extract or seeds of 1 vanilla bean
- Pinch of salt
- 1¼ cups (150 grams) type “00” flour (available here) or all-purpose flour
- ¼ cup (30 grams) unsweetened cocoa powder
White Chocolate Mousse:
- 7 ounces (200 grams) white chocolate
- 1⅔ cups (386 grams) heavy (whipping) cream
- 1 teaspoon coffee beans
- 4 teaspoons (10 grams) unsweetened cocoa powder
- ½ ounce (10 grams) cacao nibs
Make the soaking liquid:
- Sift the cocoa powder into a bowl. Pour the milk and coffee into a small saucepan, heat until almost at boiling point, then pour onto the cocoa powder, stirring continuously with a hand whisk as you do so. Set aside to cool.
Make the sponge cake:
- Preheat the oven to 350°F/180°C/160°C Fan/Gas 4. Line an 8-inch (20-cm) square cake pan with parchment paper, cut to fit. Do not butter or flour the pan, simply line it with parchment paper.
- Break the eggs into the bowl of the stand mixer. Add the sugar, vanilla, and a pinch of salt. Start the mixer on a slow speed and start to beat the ingredients together, gradually increase the speed, and continue to beat for 10 minutes, until the mixture falls from the whisk in wide ribbons and leaves a visible trace on the mixture below.
- Combine the flour and cocoa powder in a bowl, then sift one-third directly onto the whisked egg mixture. Using a silicone spatula, gently fold the flour into the mixture with an upwards motion, taking care not to knock any air out of the mixture. Sift in the remaining flour, one-third at a time, and gently fold in to combine. Pour the sponge mixture into the lined pan.
- Bake the sponge in the preheated oven for 40 minutes, or risen and firm on top—the sponge should be starting to shrink away from the pan and a skewer inserted into the center will come out clean. Do not open the oven door until the end of the cooking time to prevent the cake from sinking in the center. Let the sponge cool for 20 minutes before removing it from the pan. If necessary, run a spatula in between the pan and cake to loosen the sponge. Place the sponge on a cooling rack to cool completely.
Make the mousse:
- Finely chop the white chocolate, place in a bain-marie or double boiler, and melt over gentle heat. Pour the melted chocolate into a bowl and leave to return to room temperature. In a separate bowl, whip the cream using an electric whisk. Carefully fold the whipped cream into the cooled, melted chocolate using a silicone spatula.
Assemble the cake:
- Once cool, remove the cake from the pan and cut it horizontally into three layers. Place the bottom layer on a serving plate and brush it with one-third of the soaking liquid to moisten. Spread one-third of the chocolate mousse over the bottom sponge layer. Brush the second sponge layer with another one-third of the soaking liquid and place it on the mousse layer. Spread the sponge layer with another one-third of the mousse. Brush the final top layer of sponge with the remaining soaking liquid and place it on top of the second layer of mousse. Using a metal spatula or palette knife, spread the remaining mousse over the top sponge layer. Place the cake in the refrigerator for 4 hours.
Garnish the cake:
- Coarsely crush the coffee beans using a mortar and pestle. Decorate the top of the cake with a dusting of cocoa powder, the cacao nibs, and the crushed coffee beans.