Into a saucepan, start by adding the eggs and the sugar. Mix very well until combined.
Add the vanilla powder and the wheat flour and mix it all together again until combined.
Add the corn starch and the milk, mix again and bring saucepan over medium heat. Stir nonstop until it gains consistency and a cream is formed.
Once you’ve done that, turn off the heat and add the butter. Stir well until it melts.
Transfer the cream to a bowl and cover it with a plastic bag touching the cream. Set aside until it cools down.
Meanwhile, line an 18cm removable-bottom cake tin with parchment paper or nonstick paper all around its edges.
Now get the biscuits and break each biscuit in half. Get these halves and coat one of its sides in cream.
After that, put these biscuits into the cake tin, with the cream facing down.
Now make a 1-cm thick second layer with the cream. Then make a third layer of biscuits.
Repeat this process until you’ve used up all of the biscuits and the cream, topping it all with a final cream layer.
Crush some biscuits and pour them all over it.
Finally, take the cake tin to the fridge and leave it there for at least 8 hours. The best would be to leave it all day or overnight.
Take the cake out of the fridge, unmold and unwrap the parchment paper.
Crush some more biscuits and stick them to the sides of the pie, to taste.
Serve.