Mix the flour, sugar, and salt in a big bowl. Cut the room temperature butter into cubes and work it into the flour mixture by hand. Once it is a coarse mixture, add the egg and the vanilla.
Continue mixing by hand until the dough comes together. Shape into a disc and cover with plastic film and let it rest for 30 minutes in the fridge.
Preheat the oven to 180c degrees C
Add the vanilla to the milk and heat on a medium fire.
In the meantime, mix the yolks with the sugar and salt using a whisk. Then add the cornstarch and mix a bit more.
When the milk is hot (steamy but not boiling) take it off the fire and add 1/4 of it to the yolk mixture, mixing throughly.
Then add back all the yolk mix into the milk and mix.
Back on the stove, heat up the milk mixture while whisking until it boils. Simmer, let it boil for 1 minute and then remove.
Add the butter and mix well, cover with a plastic film touching the surface.
Roll out the tart dough with a rolling pin and some flour, then move it to a 23 cm tart dish.
Fix the edges, you will have a little bit of leftover dough (think extra cookies).
Pierce the bottom on the pan with a fork and bake (with baking beans if you have or else skip) for 25 minutes.
Once it's golden, add the pastry cream on top of the shell and bake again for 8 minutes. This will help the cream set.
Then cool in the fridge and top with the berries of your choice.
Al Baker Plain Flour 
Jenan White Eggs 15s Large 
Almarai Milk Full Fat 
Lurpak Unsalted Butter Block 
Sis Fine Granulated Sugar 
Foster Clarks Vanilla Essence 
Nezo Fine Sea Salt 
Safa Corn Starch 
Raspberry USA 
Strawberry USA 
Blueberry Peru 