Apple and Blackcurrant Pie

Pastry

• 100 g granulated sugar
• 200 g unsalted butter, chilled, cut in pieces, plus extra for greasing
• 370 g plain flour
• 1 medium egg
• 1 pinch fine sea salt

Filling

• 180 g blackcurrant jam
• 300 g cooking apples, peeled, cored and cut in slices (½ cm)

Decoration

• 2 tsp icing sugar, for dusting