Preheat the oven to 150°C fan forced. Spray 2 mini bundt cake tins with cooking spray.
In a stand mixer, beat butter and sugars on a medium speed until light and fluffy. After 2 minutes stop and scrape ingredients down into the bowl to ensure all ingredients are mixed through.
Add eggs one at a time whilst beating on medium speed.
Combine flour, cocoa powder, baking soda and salt in a separate bowl.
Add ¼ of the flour mixture, then ½ the buttermilk. Repeat until all ingredients are combined.
Fold through vanilla extract.
Spoon batter until ¾ full into the tins and bake for 20-25 minutes until a wooden pick comes out clean.
Let cakes stand for 10 minutes then invert from pans on to a cooling rack.
Ganache sauce: Bring to a gentle simmer 1 cup of cream. Pour over 250g of dark chocolate and let stand for 5 minutes untouched. Stir through with a spatula 4 Tbsp of butter.
Coffee sauce: whisk 3 cups of icing sugar, 1 tsp of lemon juice and 1 Tbsp of instant coffee (diluted with water) until a thick sauce forms. Refrigerate for 10 minutes before icing.
OR ice with store bought Dulce de Leche Sauce
OR dust with icing sugar
Top with a Ferrero Rocher and enjoy!
Store ungarnished at ambient temperature in an airtight container. Sauce should be stored in a refrigerator.