Method

• 1.
  For the custard, line a 20cm x 30cm rectangular cake pan with baking paper. Soak gelatine leaves in a bowl of cold water for 5 minutes to soften.
• 2.
  Meanwhile, place cream, milk and vanilla bean and seeds in a saucepan over medium heat. Bring to a simmer, then remove from heat and set aside. Combine cornflour, eggs and egg yolk in a bowl. Pour over hot cream mixture and whisk to combine. Return mixture to clean saucepan and place over low heat. Cook, stirring constantly with a wooden spoon, for 8 minutes or until custard coats the back of a spoon. (You may need to a whisk halfway through to prevent the cornflour from clumping.) Squeeze excess water from gelatine, then add to warm custard along with the butter, stirring until melted and combined. Strain into prepared tray and chill for 2 hours or until set.
• 3.
  To make the green tea moon cake biscuits, place all ingredients in a bowl and stir with a wooden spoon to form a sticky dough. Transfer to a floured work surface and knead into a ball. Enclose in plastic wrap and set aside at room temperature for 30 minutes to rest.
• 4.
  Preheat oven to 150°C. Roll dough out between 2 pieces of baking paper until 5mm thick. Using a 7.5cm moon cake mould, press to imprint dough. Cut around the imprint with a 7.5cm round cookie cutter. Remove the excess dough, then using the baking paper, transfer moon cake biscuits to 2 baking trays. Re-roll excess dough and repeat. Bake for 8 minutes, then reduce oven to 100°C and cook for a further 4 minutes or until firm to the touch. Set biscuits aside on trays to cool.
• 5.
  To assemble sandwiches, flip biscuits so that the smooth surface is facing up. Use a palette knife the spread coconut jam over all biscuits, then using a 7.5cm cookie cutter, cut 8 discs from custard. Place custard discs on top of jam, then sandwich with the flat side of another biscuit. Chill until ready to serve.