Equipment
Ingredients
Dry Ingredients
- 70 g cake flour
- 30 g dutch-processed cocoa powder
- 1 g salt
Wet Ingredients
- 4 eggs, separated, room temperature
- 120 g caster sugar
- 5 ml vanilla extract
Raspberry Filling and Drizzle
- 300 g frozen or fresh raspberries, thawed if frozen
- 50 g granulated sugar
- 15 ml lemon juice, freshly squeezed
- 8 g cornstarch
- 15 ml water, cold
- 100 g fresh raspberries
Nutrition (per serving)
Method
Preheat your oven to 180°C (350°F). Line the bottoms of two 20cm (8-inch) round cake pans with parchment paper, leaving the sides ungreased so the sponge can grip and rise.
Sift the cake flour, cocoa powder, and salt together into a bowl. Repeat this process twice more to aerate the dry ingredients thoroughly.
In a spotlessly clean bowl, whip the egg whites until soft peaks form. Gradually add 60g of caster sugar while continuing to whip until stiff, glossy peaks are achieved.
In a separate bowl, whip the egg yolks, the remaining 60g of caster sugar, and the vanilla extract until the mixture is pale, thick, and leaves a trailing ribbon when the whisk is lifted.
Gently fold the whipped egg yolk mixture into the stiff egg whites using a silicone spatula, using a large scooping motion to preserve the air bubbles.
Sift the aerated dry ingredients over the egg mixture in three separate additions. Gently fold after each addition just until no dry streaks remain.
Divide the batter evenly between the prepared cake pans and bake at 180°C (350°F) for 15 to 18 minutes. The cakes are done when they spring back to a gentle touch.
Allow the cakes to cool in the pans for 5 minutes, then run a knife around the edges and invert them onto a wire rack to cool completely.
While the cakes cool, combine the 300g of raspberries, 50g of granulated sugar, and lemon juice in a saucepan. Simmer over medium heat until the berries break down and release their juices.
Pass half of the hot raspberry mixture through a fine mesh strainer into a small bowl to extract a smooth coulis for the drizzle. Set the smooth coulis aside to cool.
Return the remaining unstrained raspberry mixture (with seeds) to the saucepan. Mix the cornstarch with the cold water to create a slurry, stir it into the saucepan, and boil for 1 minute until thickened into a jam-like consistency. Remove from heat and cool completely.
Place one cooled cake layer on a serving plate. Spread the thickened, cooled raspberry filling evenly over the top, leaving a small border around the edge.
Place the second cake layer on top. Drizzle the smooth raspberry coulis generously over the cake, allowing some to drip down the sides. Top with the 100g of fresh raspberries before serving.
Chef's Notes
- Fatless sponges derive all their structure and rise from whipped eggs. Ensure your bowls and beaters are completely free of grease before whipping the egg whites.
- Cocoa powder has a tendency to clump more than flour, which is why triple-sifting the dry ingredients is non-negotiable for a light texture.
- Leaving the sides of the cake pans ungreased allows the sponge batter to cling to the walls as it bakes, preventing it from shrinking or collapsing as it cools.
- For the cleanest slices, use a serrated knife and wipe the blade with a warm, damp cloth between each cut.
Storage
Refrigerator: 3 days — Store in an airtight container to prevent the sponge from drying out.
Freezer: 1 month — Freeze the unfilled sponge cakes wrapped tightly in plastic wrap. Do not freeze the assembled cake with the filling.
