Place the diced squash or the pumpkin in a large saucepan, cover with water and bring to the boil. Cover with a lid and simmer for 15 mins or until tender. Drain and leave to cool.

Heat oven to 180°C/160°C fan/gas 4. Roll out the pastry on a lightly floured surface and use it to line a 22cm loose-bottomed tart tin. Chill for 15 mins. Line the pastry with baking parchment and ceramic baking beans, dried rice or dried beans, then bake for 15 mins. Remove the beans and paper, and cook for a further 10 mins until the base is pale golden and biscuity. Remove from the oven and allow to cool slightly.

Increase oven to 220°C/200°C fan/gas 7. Push the cooled squash through a sieve into a large bowl or blend to a puree in a food processor. In a separate bowl, combine the sugar, salt, nutmeg and half the cinnamon. Mix in the beaten eggs, melted butter and milk, then add to the squash or pumpkin purée and stir to combine. Pour into the tart shell and cook for 10 mins, then reduce the temperature to 180°C/160°C fan/gas 4. Continue to bake for 35-40 mins until the filling has just set.

Leave to cool, then remove the pie from the tin. Mix the remaining cinnamon with the icing sugar and dust over the pie. Serve chilled.