“This is a riff on both a pumpkin and banoffee pie… Instead of pumpkin, I’m using crown prince squash, which is firmer and retains less water, giving you a rich, dense filling, perfect for layering with caramel. ”
Melt the butter in a large pan over a low heat. Blitz the biscuits and 100g of the hazelnuts in a food processor into crumbs, then stir into the butter. Tip into a deep, 25cm loose-bottomed tart tin, spreading it evenly and pushing it into the base and sides. Place in the fridge for 10 minutes.
To make the caramel, pour the sugar into a wide non-stick pan and let it melt over a medium heat – don’t stir it, just swirl in the pan. Once the sugar has melted and is a deep golden colour, quickly stir in the butter until combined, then whisk in the cream until smooth. Turn off the heat and let it cool for 10 minutes. Spread the caramel over the biscuit base, then firm up in the fridge for at least 1 hour.
Meanwhile, halve and deseed the squash, then cut into 3cm wedges (there’s no need to peel it). Spread them over 2 roasting trays and drizzle with the oil. Sprinkle over the cinnamon, a grating of nutmeg and a pinch of sea salt, then toss until the squash is well coated. Roast in the oven for 40 minutes, or until golden and cooked through. Remove from the oven and set aside to cool.
Scoop out the cooled squash flesh into a food processor (discard the skins), add the brown sugar and blitz until smooth. If it’s very watery, sieve out the excess liquid so you’re left with a smooth paste.
Take the base out of the fridge and spoon in the squash, spreading it over the caramel. Return to the fridge for at least 1 hour.
Meanwhile, toast the remaining hazelnuts in a frying pan over a high heat for 1 to 2 minutes, or until golden. Bash with a pestle and mortar until fine, then tip onto a lined baking tray.
In the same pan, combine 2 tablespoons of caster sugar with a splash of water and cook over a medium heat for 2 minutes, until you have a golden caramel. Pour over the nuts and set aside to cool.
Dissolve the remaining caster sugar in 3 tablespoons of water over a medium heat, swirling the pan and letting it bubble for 1 minute, until syrupy. Stir in the coffee and set aside to cool.
Whip the cream to soft peaks. Take the pie out of the fridge and spoon the cream over the squash, making peaks with the back of the spoon and rippling in the coffee syrup as you go. Sprinkle over the smashed hazelnuts, shave over the chocolate, then serve.