In a mixing bowl, combine plain flour and flaky sea salt, then rub in chilled, chopped unsalted butter until the mixture resembles breadcrumbs. Gradually add cold water until the dough holds together. Shape into a disk, wrap in plastic, and chill in the fridge for at least 30 minutes while you prepare the filling.

Preheat your oven to 400°F (200°C). Toss the peeled and sliced pumpkin with olive oil, spreading it out on a baking sheet. Roast for 25–30 minutes until tender and caramelized, turning halfway for even cooking.

In a large skillet over medium heat, add the spinach and cook for 2–3 minutes until just wilted. Remove from heat and press out any excess moisture in a colander.

In a bowl, whisk together the eggs, egg yolk, double cream, finely grated Parmesan, freshly grated nutmeg, and black pepper until smooth.

Roll out the chilled pastry into a thickness of about 1/8 inch and line your tart tins, chilling them for another 15 minutes.

Preheat your oven to 375°F (190°C). Blind-bake the pastry shells with parchment paper and weights for 15-20 minutes, then remove weights and bake for an additional 5 minutes.

Carefully fill each tart shell with wilted spinach, roasted pumpkin slices, and crumbled Gorgonzola.

Pour the custard mixture over the fillings and bake for 25–30 minutes until set and lightly golden.

Let the tarts rest for about 10 minutes before removing from the tins. Cut into wedges and serve warm.