Tip the pastry onto a work surface and roll out to a 3mm thickness. Use the rolling pin to lift the pastry up and transfer it to line a 23cm/9in loose-
Take the pastry-
For the filling, mix the orange zest and juice with the cornflour and stir to form a smooth paste. Measure 450ml/16fl oz of water into a pan and bring to the boil.
Add the orange zest cornflour mixture to the hot water and stir over the heat until the mixture has thickened, then remove from the heat. In a bowl mix together the sugar and egg yolks and carefully whisk into the orange zest mixture in the pan. Stir over a medium heat until thickened. Set aside for a few minutes and then pour into the baked pastry case.
For the meringue, whisk the egg whites in a free-
Bake in the oven for about 15 minutes until the filling is completely set and the meringue is lightly golden and crisp.