To make the pie filling, peel and grate the apples, add the sugar and cinnamon, and add everything to a pan.
On a medium heat, cook the apples until their juice is evaporated, the time depends entirely on how juicy the apples are, but it could take about 5-10 minutes or so.
Set aside and leave to cool completely.
To make the crust, beat the eggs with a pinch of salt, add the sugar and beat well until you get a smooth paste that has a pale yellow colour. You can either beat it with a whisk or a mixer.
Add the milk, vegetable oil, baking powder and half of the amount of flour and mix well.
Add the remaining flour, and use your hands to knead a dough that does not stick to the hands. You might need more flour, just add a bit more at a time.
Cut the dough into half, then roll one half with a rolling pin, and arrange it on the bottom of a baking dish that has been greased with butter (see photos in the post).
Add the cooled apple filling.
Roll the other half of the dough, then use a sharp knife to cut 12 strips of about an inch wide.
Arrange 6 strips of dough over the filling vertically - the longer strips will go in the middle, and the shorter ones towards the edges (see photo 11).
Starting from the right hand side, fold over strip no 2, 4 and 6 ( see photo 12)
Lay one unused strip perpendicularly on top, and place the folded strips back into their place.
Next, fold over strips no 1, 3 and 5 (see photo 13).
Arrange another dough strip perpendicularly, and fold the strips over again.
Repeat this process until all the dough strips have been used and you have a nice lattice top (see photo 14).
Beat the egg, then brush the pie with it.
Bake in the preheated oven at 180 degrees Celsius (350 Fahrenheit) for 20-25 minutes or until golden.
Allow the pie to cool, then sprinkle icing sugar over.