Preheat oven to 180ºC and grease a 20cm round cake tin.
In a medium saucepan over low heat, melt butter, chocolate and sugar.
Mix the melted chocolate with the almonds, salt and vanilla extract.
Beat in egg yolks, one at a time.
Whisk egg whites until stiff with an electric beater.
Mix a third of the egg white into the almond mixture and then fold in the remaining egg white.
Pour batter into a prepared tin.
Bake for 30 Minutes until a tester comes out clean.
Allow cake to cool in the tin completely.
Serve with fruit and ice-cream or on its own with a cup of coffee.