For Pastry- Blind bake the pastry case (filled with dry beans or rice over the baking paper) for 15 minutes. Remove baking paper and bake for a further 8 minutes until the pastry is pale golden. Set aside. Lower the oven to 160°C.
Turn onto a lightly floured surface, bring together until smooth, and roll out. Transfer to tart tin, and press the pastry into the tin flutes. Prick the base with a fork, cover base with baking paper and chill for one hour.
Blind bake the pastry case (filled with dry beans or rice over the baking paper) for 15 minutes. Remove baking paper and bake for a further 8 minutes until the pastry is pale golden. Set aside. Lower the oven to 160°C.
For lemon filling - While the pastry bakes, prepare filling; mix together cornflour, sugar and lemon zest in a medium saucepan. Stir in the lemon juice and orange juice mixture gradually. Cook over a medium heat, stirring constantly, until thickened and smooth. Once the mixture starts to bubble, remove from heat and beat in the butter until melted.
Beat the egg yolks and whole egg together, stir into the saucepan and return to a medium heat. Keep stirring while simmering, until the mixture thickens. Remove from heat and cool. Cover with plastic wrap and chill. Once chilled, beat with an electric mixture until smooth.
For meringue - Place the egg whites in a large clean bowl. Whisk to soft peaks, add sugar, a small amount at a time. whisking between each addition, until smooth and thick.
To finish- Pour the lemon filling into the pastry case. Top with spoonfuls of meringue. Return to oven at 160°C for 20 minutes until the meringue is slightly coloured. Allow to cool in tin for 30 minutes, remove and allow to set for 1 hour before slicing.
1 & 1/3 cups plain flour
100g Unsalted Butter, chilled and diced
1 tbsp icing sugar
1 egg yolk
1 tbsp cold water
2 tbsp cornflour
1/2 cup caster sugar
zest of two large lemons, finely grated
125ml lemon juice, freshly squeezed
strained juice of 1 orange, made up to 200ml with water