The Viennese cake is called the Sachertorte and was created by pastry chef Franz Sacher in 1832. He was asked by Prince Klemens from Metternich, the heir to a wealthy Jewish family of hoteliers, to create a new dessert for a guest because their official court chef was sick. Sacher, who was 16 at the time, created the recipe with his love for chocolate in mind and it’s said that Metternich loved it after the first bite. It is now the most famous dessert in Austria and an authentic slice can still be bought at the Hotel Sacher in Vienna and Salzburg. The exact recipe is kept a secret, but close variations are seen everywhere.
The Sachertorte consists of two layers of chocolate cake with a layer of apricot jam or cherries inside. It’s covered completely in a dark chocolate glaze.
Here is a link to a recipe:
It’s in metric measurements, but it’s the best one!