Preheat the oven to 320F (160C) and line the bottom and the sides of an 8” (20cm) springform pan with parchment paper. Wrap the pan with a piece of foil to prevent it from leaking the batter as it will be quite thin.

In a heatproof bowl, add the chocolate, butter, salt, instant coffee, and vanilla extract. Heat over a pot with simmering water or in the microwave until the butter and chocolate have melted and the mixture has a homogeneous consistency. Set aside to cool down.

Meanwhile, add the eggs and sugar to the bowl of a stand mixer fitted with a whisk attachment (or use a hand mixer), and whip on medium-high speed for 10 minutes or until the mixture has tripled in volume and is at a ribbon stage. When done, lower the speed to low and whip the mixture for an extra 1 minute.

Pour the chocolate mixture into the egg mixture. Mix it on low using a mixer or mix it with a rubber spatula until it looks homogeneous and well mixed.

Pour the cake batter into the prepared springform pan and bake for 35 minutes or until a crust has formed on the top of the cake but it is still jiggly if shaken.

Remove from the oven and let it cool down to room temperature. Then, transfer the cake to the fridge for 6 hours or overnight to set.

Dust with cocoa powder, decorate with fresh raspberries and serve.