Step 1

For the oil dough, mix all the ingredients together in a large bowl. Place the mixture between 2 sheets of non-stick parchment paper and roll out until ¾-inch in thickness, ideally into a rectangular shape.

Step 2

For the water dough, place all the ingredients in an electric stand mixer fitted with the dough hook and mix to form a dough, adding some water—up to 2 cups—in order to bind the ingredients together if necessary.

Step 3

Knead in the mixer for 10 minutes until the dough is super stretchy. You should be able to stretch the dough out between your hands to form an ultra-thin film without it breaking. Check the elasticity of the water dough by pulling it between your fingers. You should be able to stretch it into a super-thin, translucent film.

Step 4

Pack the water dough and the oil dough into separate large baking pans lined with non-stick parchment paper. Freeze for 3 hours to firm up.

Step 5

Remove the 2 doughs from the freezer and let soften slightly (but not for too long, otherwise they will be difficult to handle and require further time in the freezer to firm up again). Place the water dough on a sheet of non-stick parchment paper and, using a rolling pin, lightly roll the water dough out into a rectangle ½-inch thick. Place the oil dough on top, ensuring that there is at least a ¾-inch border of water dough all around the edge of the oil dough.

Step 6

Place a sheet of non-stick parchment paper on top of this double layer of dough and lightly roll it out to a rectangle about ½-inch thick.

Step 7

Remove the top sheet of paper, rotate the dough rectangle so that one long edge is facing you, and mark an imaginary line down the center of the dough.

Step 8

Lifting the dough by placing your hand underneath the bottom layer of paper, fold each side of the dough in to meet this imaginary line. Seal the edges.

Step 9

Fold the 2 halves over each other to form 4 layers of dough. Rotate the dough 90 degrees clockwise and lightly dust with flour. Chill in the freezer for 15 minutes to firm up slightly.

Step 10

Remove the dough from the freezer and mark into thirds. Fold one third at one end of the dough over the middle, then fold the other third over the top. Return the dough to the freezer for a further 15 minutes.

Step 11

For the filling, place the beaten eggs in a bowl. In a separate bowl, lightly whisk the sugar and custard powder into the water until the sugar has dissolved.

Step 12

Pour the sugar mixture into the eggs and stir with a spoon, then stir in the evaporated milk.

Step 13

Strain the mixture through a fine-mesh sieve to remove any lumps and then gently skim the surface with a spoon to remove any floating bubbles.

Step 14

To finish the egg tarts, preheat the oven to 350°F.

Step 15

Remove the dough from the freezer and roll it out until ⅛-inch thick. Using a round pastry cutter, cut out 30 circles that are ½-inch larger than your fluted tart molds.

Step 16

Lightly oil a tart mold, then place a pastry circle in the center. Gently push the dough out from the center to the edges, ensuring that you don't rip it. Repeat the process for all your tart molds.

Step 17

Return the tart crusts to the freezer for a final 15 minutes before filling and baking.

Step 18

Stand the tart molds on a baking pan and fill the tart crusts 70 percent full with the custard mixture.

Step 19

Bake for 5 minutes, then reduce the oven temperature to 320°F, and bake for a further 15 minutes or until the custard is just set but still retains a slight wobble.

Step 20

Turn the oven off and leave the tarts inside for 1 minute.

Step 21

Remove from the oven and let stand until warm before eating.