Preheat the oven to 160°C fan/180°C/350°F/gas 4. Grease and line the tin (pan) with non-stick baking paper.
First, make the base. Toast the hazelnuts, if using, in a dry frying pan (skillet), tossing occasionally so they don’t burn. Remove from the heat and leave to cool. Melt the butter in a small pan and set both to one side.
Separate the biscuits, remove the cream centre and discard. Place the biscuits, nuts, sugar and a pinch of salt in a food processor fitted with the blade attachment and blitz until everything resembles fine breadcrumbs. Add the melted butter, pulsing until it has been mixed through. Add the biscuit mix to the tin (pan) and press it down, covering the base in an even layer. Bake for 20 minutes, then leave to cool. Turn the oven down to 120°C fan/140°C/275°F/gas 1.
Now, make the filling. Place the chocolate in a heatproof bowl set over a pan of simmering water. Melt the chocolate, remove from the heat and set aside. Place the cream cheese, sugar, cornflour (cornstarch), cocoa, vanilla and cream in the bowl of a free-standing mixer and beat together using the paddle attachment. Add one egg at a time, continuing to beat until the mixture is smooth. Add the melted chocolate and give one final mix. Pour the thick chocolatey mixture on top of the pre-cooked biscuit base and bake for about 1½ hours or until just set. A slight wobble towards the centre should still be evident.
Switch off the oven, open the door slightly and leave the cheesecake inside to cool for an hour. This prevents the cheesecake from cracking (don’t get disheartened if it does crack, the chocolate ganache will hide it anyway). Remove from the oven and leave to cool completely at room temperature before taking it out of the tin – run a palette knife around the edge to make this easier. Place in the fridge, loosely covered for at least 6 hours to firm up.
To make the chocolate puddle, gently melt the chocolate, butter and syrup together in a heatproof bowl set above a pan of simmering water. Stir until smooth and combined, then add half the cream, stirring to incorporate completely before adding the rest. Remove the cheesecake from the fridge and dust around the edges with cocoa. Pour the ganache into the centre of the cheesecake to create a chocolate puddle. Sprinkle on some chocolate shavings if you wish. The cheesecake will benefit from reaching room temperature before slicing and serving. Serve with pouring cream or crème fraîche.
Recipe extracted from Soulful Baker by Julie Jones, published by Jacqui Small, out now.