Preheat your oven to 180°C (350°F). Grease a 9-inch round cake pan and line the bottom with parchment paper.
Melt the chopped dark chocolate and diced butter together in a heatproof bowl set over a pot of simmering water (double boiler method), stirring occasionally until smooth.
Add the egg yolks to the almond meal mixture, one at a time, beating well after each addition until smooth.
Gently fold the beaten egg whites into the chocolate-almond mixture in three additions. Fold carefully to maintain the airy texture.
Bake in the preheated oven for about 40-45 minutes, or until the cake is set and a skewer inserted into the center comes out clean or with a few moist crumbs.
Gently fold the beaten egg whites into the chocolate-almond mixture in three additions. Fold carefully to maintain the airy texture.
Egg yolks to the almond meal mixture, one at a time, beating well after each addition until smooth.
Bake in the preheated oven for about 40-45 minutes, or until the cake is set and a skewer inserted into the center comes out clean or with a few moist crumbs.
Powdered sugar if desired and serve slices of the flourless chocolate almond cake with fresh berries on the side.
In a large mixing bowl, combine the almond meal and granulated sugar. Mix well.