Method

Set the oven to 200°C/180°C fan/392°F/Gas Mark 6
Quarter, core, peel and slice the cooking and dessert apples into a bowl. Add the sugar, cornflour and cinnamon and mix well.
Unroll the pastry sheet and put it on a silicone sheet on a pizza pan (the one with holes in - helps to make sure the base is cooked), trim around the edges and use a knife to cut into the edges to pattern them.
Score a line about 1cm in from the edge of the pastry on all four sides and brush over some water.
Pile the apple mixture into the centre, spreading out to the edges. Pinch up the pastry around the edges, folding on the scored line.
Press the pastry down well.
Brush egg glaze over the turned-in pastry.
Bake the tart for 30-35 minutes, or until the pastry is golden and the apples feel tender when pierced with the tip of a knife.
Remove the tart from the oven.
Heat the apricot jam with 1tbsp boiling water and brush it over the top of the apple.
The tart is best served warm.