SERVES 6 PREP 20 mins COOK 3 hours
800g Granny Smith apples, peeled, cored, chopped 1 bunch (about 650g) rhubarb, trimmed, chopped 2 tbs caster sugar 150g (1 155g (¾ cup, firmly packed) brown sugar Large pinch of ground cinnamon 60g butter, chilled, chopped 1 egg, lightly whisked 2 tbs milk Icing sugar, to dust Vanilla ice-cream, to serve