Step 1

Pulse the flour and butter in a food processor until it resembles fine breadcrumbs. Add the beaten egg and 1 tsp cold water, then pulse again to a smooth dough – try not to overmix or the pastry will be tough. (Or make the pastry by hand: put the flour and butter in a large bowl, rub to fine crumbs with your fingertips, then mix in the egg and water using a round-bladed knife.) Wrap well, then chill for at least 1 hour or overnight (see tips).

Step 2

Heat the oven to 200°C/180°C fan/gas Roll out the chilled pastry on a dusted work surface to 3-4mm thick, then use to line the prepared tart tin. Chill in the fridge for at least 20 minutes (see Make Ahead).

Step 3

Line the chilled pastry with baking paper, fill with the ceramic baking beans or uncooked rice, then bake for 15 minutes. Remove the baking beans/rice and paper and return the tart case to the oven for 10 minutes, then remove, trim the edges and set aside. Turn down the oven to 140°C/120°C fan/gas 1.

Step 4

Meanwhile, make the filling. Put both sugars in a large mixing bowl and rub with your fingertips to remove any lumps. Add a pinch of salt, the egg yolks and custard powder, then gently mix with a wooden spoon until combined.

Step 5

Put the butter, cream and vanilla in a large saucepan over a high heat and bring to the boil. Remove from the heat and set aside to cool for a few minutes. While still hot, pour in the sugar/egg yolk mixture and stir. Pass through a sieve set over a large jug to remove any lumps.

Step 6

Spread the marmalade over the base of the pastry case, then sprinkle with the chopped candied peel. Pour in the filling mixture, transfer to the oven and bake for 1 hour until set but with a slight wobble. The filling will rise up, but as the tart cools it will sink back down. Leave to cool, then chill in the fridge for at least 1 hour before slicing (see tips). Serve with clotted or double cream.