Whisk together the eggs with the sugar for at least 5 minutes, until the mixture becomes foamy.
Meanwhile, start to chop the chocolate into small pieces with the help of a food processor. Melt the chocolate in a bowl, over a “bain-marie”.
Once the chocolate has melted, add the butter to the chocolate and stir until it is melted and smooth. Remove from the heat, so as to avoid the butter from splitting. Set aside.
Once the egg mixture is well-whipped, carefully add the ground almonds (to the egg mixture) whilst taking care to avoid lumps and losing the foamy consistency.
Once the eggs and almonds mixture is smooth, slowly add the melted chocolate and butter. Mix until creamy.
Take a cake tray or a round mould, lining it with baking parchment and slowly pour the mixture in. Spread it evenly.
Preheat the oven at 170 degrees and bake the cake at 160 degrees for at least 40 minutes. When checking in on the cake, look out for the crust which should appear on its surface. Taking a toothpick, have a poke inside – the cake shouldn’t be runny at all, only very moist. Once the cooking time is up, remove from the oven and let it cool.
Un-mould the cake, and put on a serving tray. Dust with icing sugar and serve!