Enough for 8
For the pastry
150g golden caster sugar, plus extra for sprinkling
a large egg yolk (reserve the white)
250g plain flour
level teaspoon of baking powder
For the filling
800g cooking apples
125g golden caster sugar
3 tablespoons of elderflower cordial
You will need a 24cm metal tart tin with a shallow rim.
Cream the butter and sugar together till soft and pale. Mix in the egg yolk. Mix the flour and baking powder, then add to the creamed butter and sugar. Bring the dough together and squeeze into a ball. Cut the pastry in two, putting half in the fridge, wrapped loosely in greaseproof paper.
Flour the work surface and roll out the first piece of pastry to fit the tart tin, smoothing it up the sides and over the rim. Leave any overhang in place for the time being. Pop in the fridge for 30 minutes.
Set the oven to 180C/ Gas 4. Top and tail the gooseberries. Peel the apples, quarter them and remove the cores, then slice them thickly. Put the apples, gooseberries, sugar and elderflower cordial into a stainless steel pan (aliminium will taint the gooseberries) and cook over a low to medium heat for about 10-15 minutes. The apples should be showing some signs of tenderness and the gooseberries starting to soften. Remove the fruit from the pan with a draining spoon and set aside in a bowl, leaving the juice behind.
Turn up the heat under the juice and let it boil for 5-10 minutes, until it has started to turn a little jammy, stopping before it turns brown and caramelises. Let it cool and dont worry if it sets!
Put a baking sheet into the oven. Roll out the second piece of pastry. Put the fruit into into the pastry-lined tart tin, again using a slotted spoon. Spoon over the concentrated fruit syrup. Brush the rim of the pastry with egg white, then place the second piece of the pastry over the top, pressing it down on the rim to seal the edges. Trim any overhanging pastry with a sharp knife. Cut three small slits in the centre of the pastry to let out the steam. Then if you wish decorate the top with designs made from the trimmings.
Bake the pie on the hot baking sheet for about 35 minutes. Gently beat the egg white until bubbles appear on the surface, then remove the pie from the oven, brush with egg white, scatter a thin layer of sugar over the surface and return to the oven for 5 minutes. Leave for 20-30 minutes to settle down before serving with double cream.