Citrus tart

Serves 8

(JASON LOWE)

The sharp, tangy flavour of this tart filling is the perfect contrast to the rich, buttery pastry. A lovely way to finish a celebratory meal – and you can make it in advance.

For the pastry

250g/8oz plain white flour, plus extra to dust
140g/5oz chilled, unsalted butter, cut into cubes
1 tbsp caster sugar
1/2 tsp vanilla extract
1 organic free-range medium egg yolk
A little iced water

For the filling

Finely grated zest and juice of 5 oranges
Juice of 2 lemons
300g/10oz caster sugar
5 medium eggs
9 medium egg yolks
300g/10oz unsalted butter, cut into cubes

To make the pastry, tip the flour into a food processor and add the chilled butter, sugar and vanilla extract. Pulse until you have the consistency of coarse breadcrumbs. Add the egg yolk and one tablespoon of iced water and pulse again; the pastry should begin to come together. Add a little more iced water as necessary, pulsing until the pastry forms a ball. (Be careful not to add too much water, as wet dough is difficult to work with.) Wrap in baking parchment or clingfilm and rest in the fridge for 30 minutes.

For the filling, put all the ingredients, except the butter, into a large heavy-based pan. Whisk over the lowest possible heat until the sugar has dissolved; don't let the mixture overheat, or it will curdle. Add half the butter and whisk until the mixture begins to thicken – it should coat the back of the spoon. Add the remaining butter and continue stirring until the mixture has become very thick; this will take about 10 minutes. Remove from the heat and pour into a cold bowl. The mixture will continue to thicken as it cools.

Now roll out the pastry on a floured surface to a large round, about 3mm thick. Carefully lift the dough on to the rolling pin and drape it over a 25cm fluted flan tin, about 3cm deep. Press the pastry gently into the fluted sides and prick the base with a fork. Return to the fridge to chill for a further 30 minutes.

Preheat the oven to 180C/350F/Gas 4. Line the pastry case with greaseproof paper and baking beans and bake on the middle shelf of the oven for 20 minutes. Remove the paper and beans and return to the oven for a further 10 minutes until the base is dry. Remove from the oven and spoon the filling into the pastry case. Turn the oven setting up to 220C/425F/ Gas 7 and return the tart to the oven. Cook for eight minutes, or until the top has browned slightly. Place the flan tin on a wire rack and leave the tart to cool. Serve in slices, with crème fraîche.