Roll the pastry around your rolling pin, then unroll it in a pie dish. Gently press it down to make sure it evenly covers the sies and base of the dish. Let an extra pastry overhang the dish. Chill in the freezer for 15 mins or fridge for 30 mins.

Roughly chop the chestnuts and scoop them into a large mixing bowl. Roughly chop the spinach and add it. Pick the sage leaves from the sprigs, finely chop them and add to the bowl.

Tip the roasted squash and red onion into the bowl with the spinach and chestnuts. Carefully unwrap the garlic cloves, then use a fork to press the cloves out of their skins. Mash them into a paste and add them to the bowl. Add the cornflour and toss to coat everything in it.

Crumble the Stilton into the bowl. Pour in the double cream. Gently stir to mix. Set aside. Crack the egg into a small bowl and whisk with 1 tbsp water to make an egg glaze.

Take the chilled pie crust out of the oven. Spoon in the Stilton, spinach and squash mix. Brush the edges of the pastry case with some of the beaten egg glaze. Lay the pastry lid on top of the pie, using a fork to press it to the top if the pie's sides. Brush the top of the pie with the beaten egg glaze. Use a small, sharp knife to cut a couple f slahes into the pie lid to let out any steam.

Bake the pie for 30-40 mins till golden brown and bubbling. Let the pie sit in the tin for 5-10 mins, then serve in big spoonfuls with the gravy and vegetable side dishes.

Preheat your oven to 190°C/Fan 170°C/Gas 5. Trim the squash and slice it in half. You need approximately 1kgg squash (before it's peeled and diced) to make this pie, so weigh the squash and chop the wedges until you have 800g.

Scoop out the seeds from your squash wedges and peel off the skin. Chop into bite-sized chunks, approximately 2½cm thick. Scoop them into a roasting tin. Trim, peel and chop the red onions into wedges. Add to the squash. Drizzle the veg with 2 tbsp olive oil and season with salt and pepper. Toss to mix. Wrao the garlic cloves in a twist of foil and tuck them in a corner of the tin. Roast the veg for 30 mins till just tender.

While the veg cook, rinse the baby leaf spinach, then tip into a large pan and set it over a medium heat. Season with a pinch of salt and pepper and cook, stirring often, for 10-15 mins till the spinach has wilted and reduced and any excess water has cooked off. Tip the spinach into a heatproof sieve to drain, pressing it to squeeze out any excess water. If you have a clean tea towel you don't mind staining a little, let the spinach cool then scoop it into the middle of the tea towel, then roll it up into a cylinder and twist to squeeze out as much water as possible. Set aside.

Unwrap one of the blocks of shortcrust pastry. Dust your work surface with flour and roll the pastry out to make a rectangle or circle big enough to line a 2 ltr pie dish. No flour? Roll the pastry out between two sheets of baking paper.