This is from Nigella Lawson's book, How to be a Domestic Goddess. It's quite easy to make, yet looks drop-dead impressive. Definately a cake that will cheer the soul of any adult. I used my KitchenAide mixer, so if you aren't using one, your prep time may be a bit longer.
In a separate bowl, beat the butter and Nutella together, then add Frangelico (or what you have chosen to use), egg yolks, and ground hazelnuts.
05Fold in the cooled, melted chocolate, then lighten the mixture with a dollop of egg white, which you can beat in as roughly as you want, before gently folding the rest of them in a third at a time.
06Pour into the prepared pan and cook for 40 minutes or until the cake's beginning to come away at the sides, then let cool on rack.
07Toast the hazelnuts in a dry frying pan until the aroma wafts upward and the nuts are golden brown in parts: keep shaking the pan so they don't burn on one side and stay too pallid on others.
08Transfer to a plate and let cool.
09This is imperative: if they go on the ganache while hot, it'll turn oily (believe me I speak from experience).
10In a heavy-bottomed sauce pan, add the cream, liquer or water, and chopped chocolate and heat gently.
11Once the chocolate's melted, take the pan off the heat and whisk until it reaches the right consistency to ice just the top of the cake.
12Unmold the cooled cake carefully, leaving it on the base as it will be too difficult to get such a damp cake off in one piece.
13Ice the top with the chocolate icing, and dot thickly with the whole, toasted hazelnuts.
14If you have used Frangelico, put shot glasses on the table and serve it with the cake.