Place the flour and butter into a large bowl and use your fingertips to rub the butter into the flour. Continue until the mixture resembles bread crumbs.
Slowly add the water and use a butter knife to combine.
Turn the mixture out onto a floured bench and knead until the mixture comes together and is smooth. If your dough is too dry, add a little extra water.
Cover the dough with cling wrap and place into the fridge for 30 minutes to chill. In the meantime you can preheat your oven to 190 degrees.
Lightly dust a rolling pin and your bench with flour and roll the pastry out until it's approximately 3 - 4mm thick - use your pie tin (I used a 22cm one) as a guide to how big your pasty needs to be, you want to allow a 3cm border of pastry around your dish for the sides.
Carefully place your pasty into your pie dish and gently press the pastry against the edges. Trim off any excess, but do leave approximately ½ cm of pastry hanging over the tin as it will shrink.
Place a sheet of baking paper on top of the pasty and top with baking weights or rice. Cook for 14 minutes before removing the baking paper and weights and cook for a further 6 minutes.
To make your quiche mixture, in a large jug combine the milk, eggs and salt and pepper and mix well.
Sprinkle the baby spinach, bacon pieces, crumbled feta, onion flakes, tomatoes and grated cheese over the par-cooked pastry base and carefully pour the milk mixture over the top. Place into the oven and cook for 35 - 40 minutes or until golden on top and cooked through.