Cake
1. Preheat the oven to 170°C and line an 8-inch round cake tin. In the bowl of a stand mixer, add the eggs and brown sugar. Whisk until pale and doubled in volume—this should take about 10 minutes.

2. Melt the dark chocolate and chopped butter together over a bain-marie until smooth.

3.Sift the flour and cacao powder into the melted chocolate mixture. Add the vanilla paste and salt, then stir to combine. Allow the chocolate mixture to cool slightly. Slowly pour it into the egg and sugar mixture, whisking until just combined.

4. Pour the batter into the prepared tin and bake for 25–30 minutes, or until the centre is just set. Let the cake cool completely before assembling.


Berry Jam
1.In a large pot, combine the mixed berries, caster sugar, lemon juice, rose water, and salt.

2.Cook over low heat, stirring occasionally, until the mixture is thick, sticky, and jammy—this will take around 45 minutes to 1 hour.

3. Remove from the heat and let it cool to room temperature.Transfer to the fridge to set for at least 2 hours.


Salted Chocolate Ganache
1. Pour the cream into a saucepan and bring it to a gentle simmer. As soon as the cream starts to boil, pour it over the chopped dark chocolate and salt. Let it sit for 1 minute, then whisk until the chocolate is completely melted and smooth. Allow to cool before using.

Swiss Meringue Buttercream
1. Add the egg whites, caster sugar, and brown sugar to a large, clean, grease-free bowl. (Be careful not to get any egg yolks into the mixture.)

2.Place the bowl over a double boiler and whisk constantly until the sugar has completely dissolved—this should take about 10 minutes. You can test it by rubbing a small amount between your fingers; it should feel smooth, not grainy. Remove the bowl from the heat and transfer it to a stand mixer fitted with the whisk attachment. Whisk on high speed until the mixture is glossy, doubled in volume, and cooled to room temperature. This will take around 15 minutes—don’t rush this step. Add the sifted icing sugar and whisk for another 5 minutes.

6. With the mixer running, add the softened butter one tablespoon at a time. The mixture may look curdled at first, but keep going—it will come together.

7. Once all the butter is incorporated, continue whisking for 10–15 minutes, until the buttercream is smooth, silky, and evenly combined.

8.Add in the vanilla paste and salt. Mix to finish.


Assembly
1.Once the cake is fully cooled, carefully slice it in half horizontally.

2.Spread a generous layer of the chilled berry jam over the bottom half, followed by a layer of the cooled ganache.

3.Place the top layer of the cake over the filling.

4. Use the Swiss meringue buttercream to cover and decorate the cake however you like.