Rich chocolate sponge is topped with a light raspberry mousse made with fresh raspberries. After an overnight chill, this two-layer cake sets and slices cleanly.
3platinum-grade gelatin sheetsabout 0.17 ounces (4.9 g) total
480mlheavy cream
Decoration
3fresh raspberries
Instructions
Preheat the oven to 180 °C and line an 8×8 inch (20×20 cm) square cake pan with parchment paper. In a large mixing bowl, whisk 3 large eggs, 60 g granulated sugar, 50 g light brown sugar, and 1 teaspoon vanilla extract with a hand mixer until pale, fluffy, and slightly thickened.
Sift the 65 g all-purpose flour , 15 g unsweetened cocoa powder, 1 teaspoon baking powder, and ¼ teaspoon salt, over the egg mixture. Add the ½ teaspoon instant coffeeix just until combined. Gently fold in the 75 g dark chocolate , melted.
Pour the batter into the prepared pan and smooth the top. Bake for 25 minutes, or until a toothpick inserted in the center comes out clean. Leave the chocolate sponge to cool completely in the pan on a wire rack.
Purée the 400 g fresh raspberries in a food processor until smooth, then strain through a fine-mesh sieve to remove the seeds. Heat the raspberry purée with the 1 tablespoon lemon juice and 100 g granulated sugar over medium heat, stirring until the sugar dissolves.
Soak the 3 platinum-grade gelatin sheets in cold water for about 5 minutes. until softened. Squeeze out the excess water, add the gelatin to the warm raspberry mixture, and stir until completely dissolved. Remove from the heat and leave to cool.
Whip the 480 ml heavy cream to stiff peaks. Fold the cooled raspberry mixture into the whipped cream in three additions until evenly combined.
Remove the cooled sponge from the pan and trim the edges. Line an 8×8 inch (20×20 cm) square cake mold with plastic wrap, place the sponge inside, and spread the raspberry mousse evenly over the top.
Refrigerate the chocolate raspberry mousse cake for 8 hours or overnight, until set. Unmold the cake, decorate with the 3 fresh raspberries, slice, and serve chilled.
Notes
Gelatin strength: Three platinum-grade sheets. Another gelatin grade may produce a different set.Protect the sponge: Fold the dry ingredients and chocolate gently to preserve the air incorporated into the eggs.Cool the raspberry mixture: Let the mixture cool before folding it into the cream so the mousse keeps its whipped texture.Clean slices: Use a sharp knife and wipe the blade between cuts to keep the two layers clearly defined.