Method

• 1.
  For the shortcrust pastry, place butter and sugar in stand mixer fitted with paddle attachment and beat for 2 minutes or until pale and fluffy, scraping down edges of bowl at least once. Add egg and beat until well combined. With the motor running slowly, add flour until pastry starts to come together. Remove and shape into a disc. Enclose pastry in plastic wrap and chill for 30 minutes.

• 2.
  Preheat oven to 180°C and grease a 24cm loose-bottomed fluted tart pan.
• 3.
  On a lightly floured surface, roll pastry out to 5mm thick and use to line prepared pan. Trim excess pastry and chill for a further 15 minutes. Line the pastry with baking paper and pastry weights or uncooked rice. Bake for 20 minutes, then remove weights and paper, and return to oven for a further 15-20 minutes or until pale golden and dry. Remove from oven and set aside to cool slightly.
• 4.
  Meanwhile, for the custard filling, place milk in a small saucepan over medium heat and bring to just below the boil. Whisk custard powder, cornflour and ¼ cup (60ml) water in a small bowl. Add cornflour mixture to milk and cook, whisking constantly, for 2 minutes or until thickened. Remove from heat and set aside to cool for 5 minutes.
• 5.
  Meanwhile, place butter and sugar in cleaned stand mixer fitted with the paddle attachment and beat until smooth. Add cooled custard mixture and beat to combine. Working quickly, pour into tart shell and set aside to cool.
• 6.
  For the orange filling, place 1 cup (250ml) water, orange juice and sugar in a medium saucepan over medium heat and bring to just below the boil. Whisk cornflour and ¼ cup (60ml) water in a bowl and add to orange juice mixture. Cook, whisking constantly, for 2 minutes or until thickened. Set aside to cool for 5 minutes, then add butter, whisking to combine. Slowly pour over custard filling. Set aside to cool for 10 minutes, then chill for 1 hour or until firm.
• 7.
  Cut into wedges to serve.