Make the pastry.   Place the flour, icing sugar and cubed chilled
butter into a good sized bowl.  Rub the butter into the flour between
your thumb and finger tips until the mixture resembles breadcrumbs.
Make a well in the centre of the breadcrumbs and add the beaten
eggs.  Using a rounded pallet knife, or the back of a table knife, cut through the mixture
to make a dough.  You may need to add a little cold water (perhaps 1 or 2 teaspoons) to
fully bring the mixture together.  Tip the dough onto a lightly floured
work surface and lightly knead the dough for 10 seconds.  Shape the
pastry into a ball and flatten into a disc.  Wrap in cling film and
place into the fridge to chill for at least 30 minutes, (see note b).

Make the crumble.  Place the flour and chilled butter into
a good sized bowl.  Use a knife to cube the butter.  Rub the butter into
the flour between your thumb and finger tips, until the mixture
resembles fine breadcrumbs.  Add the sugar and porridge to the crumble
mixture and stir together until well incorporated.  Set aside.

Make the custard.  (Follow the packet instructions if using your preferred brand).  Place the custard powder and sugar into a bowl.  Add 3 tablespoon of the cold milk and stir to make a smooth paste.  Pour the remaining milk into a pan and set on the hob over a medium flame.  Once the milk is just about to come to the boil pour it over the custard paste mixture.  Stir thoroughly to make a smooth custard.  You're aiming for the custard to be moderately thick.  If the custard is a little runny, pour it back into the pan and set over a low heat.  Stir constantly with a wooden spoon until it starts to thicken.  Once ready pour it back into the bowl.  Cover the custard with clingfilm, ensuring that the film is in direct contact with the custard to prevent it from forming a skin as it cools.  Set the bowl aside. (See note c below)

Remove the pastry from the fridge and divide into 5 pieces of roughly
equal size.  Place one portion onto a lightly floured work work surface.  Lightly cover the remaining 4 which have been set aside with the cling film. Roll the
pastry out until it is about 2-3mm thick.
Wrap the pastry around the rolling pin, lift it up (using the pin) and
place into the flan tin.  Gently tease the pastry into the case so that
it sits into the edges well and picks up the shape of the fluted sides.
If the pastry tears, patch it with surplus pastry.  Avoid stretching
the pastry.  Line the remaining tart cases in the same way.

Trim away the excess pastry.
Use a pair of clean scissors to trim away the bulk of the excess pastry
which over hangs the sides of the tart cases.   Don't worry about
making it neat as the pastry will be trimmed neatly after it has been
blind baked.  Use a fork to gently prick the
pastry base.  Place into the fridge to chill for at least 10 - 15
minutes.

Pre-heat the oven to 190c / 170 fan /
Gas 5.  Place a baking tray onto the middle shelf which is large enough
to house the tart cases.

Prepare to blind bake the pastry.  Remove
the lined tart tins from the fridge.   Cut 5 squares of grease proof paper
large enough to cover the base and sides tart cases.  Scrunch up a piece and open it
out.  Gently lay it on top of the pastry, easing it into the edges.
Weigh the paper down with baking beans or uncooked rice or pasta.  Repeat with the remaining 4 cases.

Blind bake the pastry.
Place the cases into the
oven on the heated baking tray(s) and cook for 14 minutes.  After 10
minutes, you may need to rotate the cases.  Remove from the oven and
lift out the greaseproof paper which holds the baking beans / rice.
Allow the pastry cases to cool.  Return the baking tray to the oven.

Reduce the oven temperature to 180c / 160 fan /
Gas 4.

10.  Prepare the bilberries.  Gently wash the bilberries, removing
any leaves, stems or spoilt fruit.  If using jarred bilberries drain & rinse the berries.  Dry them gently with kitchen roll.  Sprinkle the sugar and cornflour over the berries.  Gently stir with a spoon to combine.  Aim to evenly distribute the cornflour as best you can.

11. Trim the cooked pastry cases.   Use a small sharp knife to trim the
excess cooked pastry from the pastry cases.  Hold the knife
horizontally.  Slowly and carefully trim away the excess so that the top
of the pastry case is flush with the metal housing.  If the pastry cracks a little patch it with a little of the raw pastry trimmings.

12.  Stir the custard.  Remove the clingfilm from the now cool custard.  Use a spoon to mix the custard thoroughly.

13.  Assemble the Bilberry & Custard Crumble Tarts.   Divide the prepared bilberries between the five tart cases, ensuring that the berries make an even layer in the pastry case.  Place a tablespoon of custard onto the berries.  Use the back of the spoon to gently spread it out.  Avoid having the custard touch the metal tart case as this will make removing the baked tart from the case more difficult.  Top the tarts with the crumble mixture, teasing it to the edge of the tart case to ensure that the contents are completely covered.

14.  Bake.
Place the tart cases into the oven (on the preheated baking tray) and
bake for 30 - 35 minutes.  Check the tarts after 25 minutes of baking,
you may need to rotate the tarts at this point.  The tarts are ready
when the crumble topping is a pale golden
brown.  Remove from
the oven and set aside on a cooling rack to cool.

15.  Remove from the tart cases.  After 4 or 5 minutes of cooling remove the tarts from their cases.  Gently return them to the cooling rack to finish cooling.

Enjoy!