Ingredients
Equipment
Method
- Preheat your oven to 350°F (175°C). Grease and flour an 8-inch round cake pan, or line the bottom with parchment paper.
- In a large bowl, whisk together the all-purpose flour, granulated sugar, unsweetened cocoa powder, baking soda, and salt. Ensure there are no lumps.1.5 cups all-purpose flour, 1 cup granulated sugar, 0.5 cup unsweetened cocoa powder, 1 teaspoon baking soda, 0.5 teaspoon salt
- In a separate medium bowl, whisk together the warm water, vegetable oil, white vinegar, and vanilla extract.1 cup warm water, 0.5 cup vegetable oil, 1 tablespoon white vinegar, 1 teaspoon vanilla extract
- Pour the wet ingredients into the dry ingredients and whisk until just combined and smooth. Be careful not to overmix.
- Pour the batter into the prepared cake pan and bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean.
- Let the cake cool in the pan for 10-15 minutes, then carefully invert it onto a wire rack to cool completely. Once cooled, you can trim the domed top to create a flat surface if desired.
- In a small saucepan, combine the fresh or frozen raspberries, ¼ cup granulated sugar, and lemon juice. Cook over medium heat, stirring occasionally, until the raspberries break down and the mixture is slightly thickened, about 5-7 minutes. For a smoother coulis, you can pass this mixture through a fine-mesh sieve to remove the seeds, but this is optional.1.5 cups fresh or frozen raspberries, 0.25 cup granulated sugar, 1 tablespoon lemon juice
- While the raspberry mixture is cooking, sprinkle the unflavored gelatin powder over the 3 tablespoons of cold water in a small bowl. Let it sit for 5-10 minutes until it swells and becomes firm.1.5 teaspoons unflavored gelatin powder, 3 tablespoons cold water
- Gently warm the raspberry coulis (if it has cooled) or add the bloomed gelatin directly to the warm raspberry mixture. Stir continuously until the gelatin is completely dissolved. Set aside to cool to room temperature.
- In a large, chilled bowl, whip the cold heavy whipping cream with an electric mixer on medium-high speed until soft peaks form.1.5 cups heavy whipping cream
- Gradually add the powdered sugar and the vanilla extract to the whipping cream and continue whipping until medium-stiff peaks form. Be careful not to over-whip, or you’ll get butter.0.5 cup powdered sugar, 1 teaspoon vanilla extract
- Once the raspberry mixture has cooled to room temperature (this is important to prevent it from melting the whipped cream), gently fold it into the whipped cream mixture. Start by folding in about one-third of the raspberry mixture to lighten the cream, then add the remaining raspberry mixture and fold until just combined and no streaks remain.
- Place the cooled chocolate cake base back into the cake pan (you may want to clean and dry it first, or use a springform pan for easier removal). Pour the raspberry mousse evenly over the cake base. Smooth the top with a spatula.
- Cover the cake pan with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, until the mousse is set and firm.
- Heat the ½ cup of heavy whipping cream in a small saucepan over medium heat until it just begins to simmer around the edges. Do not boil.0.5 cup heavy whipping cream
- Place the finely chopped semi-sweet chocolate in a heatproof bowl. Pour the hot cream over the chocolate and let it sit for 5 minutes without stirring.4 ounces semi-sweet chocolate
- Gently whisk the mixture until it is smooth and glossy. If there are any stubborn chocolate bits, you can briefly microwave it in 10-second intervals, stirring in between, until smooth.
- Let the ganache cool until it reaches a thick but pourable consistency. If it’s too hot, it will melt the mousse; if it’s too cold, it will be too stiff to pour.
- Once the mousse is set, carefully remove the cake from the pan. If you used a regular cake pan, you may need to run a knife around the edge to loosen it before inverting onto a serving plate. If you used a springform pan, simply release the sides.
- If using, spoon the cooled ganache into a piping bag or a Ziploc bag with the corner snipped off. Drizzle the ganache around the top edge of the cake, allowing it to drip down the sides. You can also pour a little in the center and spread it evenly.
- Decorate the top of the cake with fresh raspberries.0.5 cup fresh raspberries
Notes
Leftover cake should be stored in an airtight container in the refrigerator for up to 3-4 days. Freezing instructions are provided in the article for the cake base or assembled cake, with notes on potential texture changes.
