Put the flour, icing sugar and salt in the bowl of a food processor and pulse a couple of times to combine

Scatter the pieces of butter over the dry ingredients and pulse until the butter is cut in coarsely - you'll have pieces the size of oatmeal flakes and pea-size pieces and that's just fine

Stir the eggs, just to break them up, and add it them little at a time, pulsing after each addition

When the eggs are in, process in long pulses - about 10 seconds each - until the dough, which will look granular soon after the egg is added, forms clumps and curds

Just before your pastry reaches this clumpy stage, the sound of the machine working the dough will change, so listen out

Turn the dough out onto a work surface. Very lightly and sparingly - make that very, very lightly and sparingly - knead the dough just to incorporate any dry ingredients that might have escaped mixing

Butter the pie dish and press the dough evenly along the bottom and up the sides of the dish and over the rim. Don't be stingy - you want a crust with a little heft because you want to be able to both taste and feel it. Also, don't be too heavy-handed - you want to press the crust in so that the pieces cling to one another and knit together when baked, but you don't want to press so hard that the crust loses its crumbly shortbread-ish texture

Freeze the pastry for at least 30 minutes, preferably longer, before baking

Preheat the oven to 175ºC/375ºF/Gas mark 4

Butter the shiny side of a piece of aluminium foil and fit the foil tightly against the pastry

Bake the pastry for 25 minutes, then carefully remove the foil. If the pastry has puffed up, press it down gently with the back of a spoon

Bake for another 3 to 5 minutes. Allow to cool before adding the pie filling

Combine the sugar, flour and cinnamon

Stir in the blueberries

Turn into pastry-lined pie dish and dot with butter

Roll out the remaining piece of pastry into a round and, using the rolling pin, carefully lower the pastry over the filling

Press the pastry lid into the pastry bottom either with your thumbs or a fork. Trim the excess and brush the top with a little milk

Bake at 175ºC/375ºF/Gas mark 4 for 25-30 minutes or until crust is brown and juice just begins to bubble through slits in the crust

Boil the milk in a medium-sized saucepan. Allow to cool a little

Mix yolks, sugar and vanilla in a basin before adding to the milk

Put the saucepan back on a low heat and stir with a whisk or wooden spoon until the desired thickness. Do NOT boil

Pass through a fine sieve into a serving jug