Candied squash cheesecake

Serves 8 For the base — butter, for greasing

— 50g walnut halves — 150g ginger-nut biscuits — 80g unsalted butter, melted For the filling — 1 butternut squash, peeled, seeds and stringy bits removed

— 50g unsalted butter

— 50g soft light-brown sugar — 200g mascarpone — 125g crème fraîche

— 70g mild feta, crumbled — 2 large eggs, separated — 1½ tbsp honey — candied walnuts, to decorate (optional) For the cinnamon sugar — 1 tbsp icing sugar

— ½ tsp ground cinnamon Preheat the oven to 180C/160C fan/gas mark 4. Butter a 23cm springform or loose-based cake tin and line it with baking paper.

For the filling, weigh out 700g of peeled butternut squash and cut it into large chunks. Reserve the rest for another recipe.

Melt the butter and half of the sugar in a medium roasting tin. Add the squash to the tin and toss to coat. Bake for 30-40 minutes, or until the squash is very tender. Toss every now and then to ensure even cooking, and if it looks as if it’s browning, lower the oven temperature; you want it to be soft and translucent, not crisp and brown.

Cool the squash briefly then tip into a food processor, together with any remaining juices from the roasting tin, and blitz to a very smooth purée. Scrape into a sieve set over a sink or bowl and leave to drain and cool completely. Refrigerate until needed. (You can prepare the squash a day ahead of time, which has the benefit of concentrating the flavour – discard any liquid that separates out from the flesh before using.)

To make the cheesecake base, spread the walnuts out on a small baking tray and toast in the oven for 8-10 minutes, or until they are darkening. Let them cool, then tip into a food processor and blitz to coarse, rather chunky crumbs. Take care not to over-process them. Tip into a mixing bowl.

Put the ginger biscuits into the food processor and blitz to medium-fine crumbs. (Alternatively, put the biscuits into a plastic bag and whack them with a rolling pin.) Add them to the walnuts, then stir in the melted butter evenly. Tip into the prepared tin and press in firmly and evenly. Put in the oven for 15 minutes to par-bake.

While the base is par-baking, finish the filling. Combine the mascarpone, crème fraîche, feta, egg yolks and honey in a food processor and blitz together until evenly blended. Mix in the squash purée, just until evenly combined.

Put the egg whites into the bowl of an electric mixer and whisk until they start to froth. Then, with the motor running, scatter over the rest of the sugar and continue whisking to medium-stiff, glossy peaks.

Add a large spoonful of meringue to the squash filling and mix in to slacken. Add the rest of the meringue and fold in gently but evenly with a large metal spoon, taking care not to lose volume.

Remove the base from the oven and lower the oven temperature to 160C/140C fan/ gas mark 3. Pour the filling into the tin and bake for around 40 minutes, or until the cheesecake is set, but still a little soft and wobbly in the centre. Turn off the oven and prop the door slightly ajar with the handle of a wooden spoon. Leave well alone until the cheesecake has cooled completely. This should help to prevent the surface cracking, but it is not the end of the world if that does happen.

Once the cheesecake is completely cold, carefully remove it from the tin. Refrigerate until ready to serve, bringing to room temperature about 20 minutes before eating.

For the cinnamon sugar, mix together the icing sugar and cinnamon and sift over the cheesecake just before serving. Finish with candied walnuts, if using.