To make the filling, heat the oil in a large non-stick frying pan.
Cut the bacon rashers in half and fry over a medium heat for 4–5 minutes until the fat is golden and crisp, turning them once.
Remove the bacon from the heat and leave to cool. Place a sturdy baking tray in the oven and preheat to 190C/375F/Gas 5.
For the pastry, pulse the flour, salt and butter in a food processor until the mixture resembles fine breadcrumbs.
Whisk the egg with a tablespoon of cold water and pour onto the flour and butter mixture with the motor running. Continue blending until the dough begins to form a ball.
Turn the pastry out onto a lightly floured board, knead quickly into a ball and cut in half.
Roll out one half until it is about 0.5cm/¼in thick and line a greased 23cm/9in pie plate, leaving any excess pastry overhanging the edge.
Scatter the bacon loosely over the pastry case. Gently break six of the eggs into the pastry case, spacing them evenly between the bacon rashers.
Beat the remaining eggs with the milk and plenty of salt and pepper.
Slowly pour the beaten eggs into the pastry case, stopping every now and then to allow the beaten egg to find its way between the whole eggs and the bacon. Leave 2–3 tablespoons of the mixture in the bowl for glazing the top of the pie.
Roll out the rest of the pastry to make a lid for the pie. Brush the edge of the pastry case with beaten egg and milk and gently lift the pastry lid over the filling.
Press the edges firmly to seal, then trim. Use a fork to firmly seal the edge all the way around the pie then brush the top with the remaining beaten egg to glaze.
Bake the pie on the preheated baking tray for 45–55 minutes until golden-brown and cooked through.
Test by piercing the centre with a sharp knife – the filling should be just set. If it’s still runny, put the pie back in the oven for a few minutes. Leave to stand for at least 15 minutes before serving.