Requires: 24cm round cake pan, electric mixer (or hand beater)
Preheat oven to 180°C conventional oven (400° Fahrenheit/Gas 6). Grease a 24cm round cake pan by lightly buttering the base and sides with margarine or butter. Line the base with baking paper, then lightly butter over the baking paper. Add a tablespoon of 00 flour, then turn and shake the tin to coat the butter in flour on the base and sides of the cake pan.
Place the hazelnuts into a food processor and process until it reaches your required consistency of roughly chopped, medium or finely ground. Set aside.
Using an electric mixer or hand beater, beat the egg whites with a pinch of salt until stiff peaks form. With the mixer (or hand beater) running, add the egg yolks, one at a time. Add the sugar, one tablespoon at a time, beating well after each addition.
Use a wooden spoon to stir in the flour, one tablespoon at a time. You want to see air bubbles rise to the surface of the cake mixture before adding additional tablespoons of flour. Stir in the lemon juice and margarine (or butter) until well combined. Stir the sifted baking powder into the cake mixture, then fold in the hazelnuts.
Note: 00 is a powder-fine Italian type of flour. It is made from soft wheat varieties, and is frequently used in Italian desserts and pastas. 00 flour is available in most supermarkets, Italian food stores and gourmet delicatessens.
Pour the cake mixture into the prepared cake pan. Bake for 45 minutes or until a skewer inserted into the centre of the cake comes out clean. Allow to cool in the cake pan for 10 minutes, then transfer to a wire rack to cool completely.
Meanwhile, for the ganache topping, place the dark chocolate in a heatproof bowl set over a pan of simmering water (don’t let bowl touch the water). Cook, stirring using a metal spoon, until the chocolate has melted to a smooth consistency. Remove from the heat and stir the thickened cream into the melted chocolate. Pour the ganache topping over the top and sides of the Torta di nocciole (hazelnut cake). Allow the chocolate ganache to set for 1 hour before serving – buon appetito.
100g dark chocolate (70% cocoa), chopped|120g thickened cream