This week's dish is a marriage of flavours from south-west France, best made with prunes from Agen in the Lot-et-Garonne, southeast of Bordeaux.

So associated with prunes is the town that it even hosts a festival dedicated to the dried plum every September. Agen prunes are synonymous with quality and give the optimal balance of sweetness and acidity for this rich tart.

Prune and armagnac custard tart

Serves 8

Sweet pastry

1tbsp melted butter, for brushing the pastry ring

250g unsalted butter

125g icing sugar

500g plain flour

2 small eggs

Filling

200g Agen prunes, stoned

200ml water

50ml armagnac

300ml milk

300ml double cream

1 vanilla pod

2 eggs

2 egg yolks

50g caster sugar

Brush a 22cm x 5cm pastry ring with the melted butter, lightly dust it with caster sugar and place it on a heavy baking tray then refrigerate.

To make the pastry, soften the butter then place it in a mixing bowl with the icing sugar and beat with a wooden spoon until well incorporated. Once smooth, add the flour and rub together with your hands until the mixture resembles breadcrumbs.

Next beat the eggs lightly in a small bowl then add them to the mixing bowl, working the flour mixture in gradually until it becomes a smooth dough. Be careful not to overdo it, as this will make the pastry tough and chewy. Once the dough is formed, wrap it in clingfilm and refrigerate for 30 minutes.

Once rested, roll out the pastry on a lightly floured work surface, moving and rotating it until you have a circle of pastry roughly 1cm thick.

Carefully lift the pastry and drop it into the tart ring, using your fingers to push the pastry against the sides. You should be left with a slight overhang of pastry over the tart ring. Put the tart back in the fridge for 15 minutes. Set the oven to 180C/gas mark 4.

Once the pastry has rested, trim off the excess pastry with a small knife then line the tart case with greaseproof paper and add baking beans.

Place the tart ring in the oven for approximately 15 minutes or until the pastry is golden and cooked, then remove the greaseproof paper and baking beans and place the pastry back in the oven for 3-4 minutes to cook the base thoroughly.

For the filling, roughly chop the prunes and place them in a large pot with the water and armagnac, then bring it to the boil. Once boiled, drain the prunes and set them aside, discarding the water.

Put the milk and cream in a large saucepan on a low to moderate heat.

Split the vanilla pod in two and scrape out the seeds, then put the seeds and the pod into the pan and stir to infuse.

Crack the eggs into a large bowl with the yolks and whisk in the caster sugar.

Gently bring the cream to the boil; once boiled, remove the vanilla pod and pour the cream over the eggs while whisking until fully incorporated. Return the mixture back to the saucepan and cook over a low heat, continuously stirring the mix to avoid it scrambling.

When the mixture has thickened and can coat the back of the spoon it is ready. To check, remove the spoon from the pan and run your finger along the back - if the custard doesn't fill in the line then it's done.

Now remove the pan from the heat and mix in the prunes. Pour the mixture into the tart case and fill to the top. Lower the oven temperature to 140C/gas mark 1 then place the tart in the oven for 40-45 minutes or until the filling has set. Allow the tart to cool before serving.