To make the Pastry, cut the cold butter into small cubes. Rub with the flour and salt, or mix in a food processor to a breadcrumb texture. Add enough chilled water to form a pastry. Wrap in clingfilm and place in the refrigerator for an hour to rest.
Grease a 24 cm tart tin. Roll the dough out on a lightly floured work surface and line the prepared tart tin. Return to the fridge for another hour.
Preheat the oven to 160°C. Line the tart shell with baking paper and dried beans or rice (or pastry weights) and blind-bake for 30–45 minutes. When the sides are cooked, remove from the oven and remove the beans or rice.
Prick the base of the tart and brush with a little egg white, then return to the oven for another 30 minutes until the pastry shell has dried out.
To prepare the Filling, drizzle the pumpkin with a little olive oil, a sprinkling of salt and a few sage leaves.
Roast in an oven preheated to 180°C until soft and lightly caramelised. Place the pumpkin in the cooked shell.
Mix the eggs and cream and gently pour over the pumpkin. Drop the gorgonzola here and there over the pumpkin and bake at 160°C until the egg and cream is set.
Let cool and serve with a delicate salad.