Serves 4

Blueberry pie is a comforting sort of dessert, especially with thick soured cream or crème fraîche in the American style. Individual tarts travel well if you're risking one last picnic to spin out summer as long as possible. Instead of fresh Dorset blueberries - which are harvested into September - you could use frozen ones, or make the pie with blackberries, but you'll probably need to add more sugar to taste for the filling. The English blueberries are sweeter than imports. Either make 4 individual pies in 10cm x 3cm-deep tins, or one large one in a 16-18cm x 4cm-deep tin.

for the pastry

125g unsalted butter
180g caster sugar
1 large egg, beaten
250g plain flour
flour for dusting

600g blueberries, fresh or frozen
120g caster sugar
1tbsp water
1tsp arrowroot or cornflour
1 egg white, mixed with 1tbsp caster sugar
150g sour cream or crème fraîche
Icing sugar for dusting

First make the pastry. In a food processor, mixer or by hand, cream the butter and sugar together until smooth and creamy. Slowly add the beaten egg - scraping the sides of the bowl every so often if you are using a mixer - until they are mixed well, then slowly fold in the flour. Mould the dough into 2 balls, wrap it in clingfilm and refrigerate for 30 minutes.

Roll out the pastry on a floured table to about 3mm thick. Cut 4 discs large enough to line 10cm x 3cm-deep individual tart tins and leaving about 1¿2cm overlapping the edge. Cut 4 more discs to fit the tops. Or adjust accordingly for one larger tart tin. Lightly grease the tins with butter and line with the larger disc of pastry to just above the top of the tin. Leave to rest for 1 hour in the fridge.

Meanwhile put the blueberries into a saucepan with the caster sugar and water. Bring to a simmer and cook for 2 minutes. Dilute the arrowroot with a little water, add to the blueberries and simmer for 2-3 minutes stirring occasionally. Transfer into a bowl and leave to cool.

Pre heat the oven to 200°C/390°F/Gas mark 6.

Remove the pastry from the fridge about 10-15 minutes before you need it, in order to soften, then spoon the blueberry mixture into the pie linings, taking care not to include too much juice. Brush round the edges of the pie tops with the sweetened egg white then turn over, laying the lids on to the filling, and sealing the sticky edges together with your fingers. Brush the tops with more egg white, make a small slit with the point of a knife in the centre then bake the pies on a tray for 20- 25 minutes until golden. Turn the oven down a little if they begin to colour too much or cover them with foil. Leave to rest for about 15 minutes before turning out of the moulds.

Serve dusted with icing sugar and sour cream or crème fraîche