Indulge in a rich and velvety raspberry chocolate mousse for a romantic Valentine's Day dessert. Start by melting dark chocolate and let it cool slightly. In a separate bowl, whip heavy cream until soft peaks form. Gently fold in the melted chocolate and fresh raspberry puree. Divide the mousse into individual serving glasses and refrigerate for a few hours until set. Top with fresh raspberries and a sprinkle of cocoa powder before serving.