Preheat the oven to 170C. Line a tin with baking paper on the bottom and sides.

Place the butter and sugar in the bowl of a stand mixer with the paddle attachment and beat for 4-5 minutes, until light and fluffy. Add the eggs one at a time, beating well between each addition. Mix the walnuts, almonds, flour, baking powder and salt in a separate bowl. Add the dry ingredients to the big bowl and fold to combine. Add the chopped dark chocolate and Disaronno and fold to combine. Tip the cake mixture into the tin and use a palette knife to level the top.

Bake for 30-40 minutes, until golden brown and a skewer inserted into the centre emerges clean. Allow to cool for 10 minutes before turning out on to a wire rack to cool fully.

For the icing, melt the remaining chocolate with the neutral oil in a heatproof bowl in 30-second bursts in the microwave. Add the toasted chopped nuts and stir to combine. Pour this mixture over the cooled cake, using a palette knife or the back of a spoon to smooth it over the top and down the edges. Allow to set at room temperature before serving.