Heat oven to 200C/fan 180C/gas 6. Dust the work surface with a little flour, then roll the pastry out to the thickness of a £1 coin. Use to line a deep, 23cm loose-bottom flan tin and chill until firm. Line with greaseproof paper and a layer of baking beans, then bake for 20 mins. Remove the paper and beans, then return to the oven for 5 mins until pale golden in colour. Leave to cool.
For the filling, cut the passion fruit in half, then scoop the pulp of 10 into a sieve over a large jug. Rub the pulp and juice through the sieve; discard the seeds. Scoop the pulp and seeds of the remaining fruit into the juice. You should now have 150ml in total – so make up with orange juice if you don’t have enough. In a pan, mix the cornflour with the sugar, then gradually stir in 200ml cold water followed by the passion fruit. Cook over a medium heat, stirring, until the mixture boils and thickens. Take the pan off the heat and whisk the yolks into the hot mixture.
Reduce oven to 180C/fan 160C/gas 4. For the meringue, whisk the egg whites into stiff peaks, then gradually whisk in
the sugar until thick and glossy. Reheat the filling briefly, then spread over the pastry base. Spoon the meringue over the filling, starting from the pastry edge and working your way into the middle, then gently swirl the spoonfuls together. Bake for 20 mins until the meringue is lightly golden. Serve warm or cold.