First, preheat the oven to about 200 degrees Celsius (392 degrees Fahrenheit).
Whisk eggs and sugar until fluffy.
Sift flour, cocoa, and baking powder into the egg mixture and fold it gently.
Now take a new springform pan, grease the edges, and line the bottom with baking paper.
Pour the batter into the form and bake the cake for 5-7 minutes.
Remove the cake layer and let it cool.
Once the cake layer and coffee mousse have cooled, place the layer on top of the mousse and put the cake back in the fridge.
In the meantime, start making the raspberry mousse.