Baking a deep Quiche. I blind baked the pastry, and pre-cooked the chopped bacon, then added my fillings to the pastry. Cookbooks all say cook for 40mins at 140Fan. Not a chance. It was too soggy, and took over 100mins at 140! On completion it still looked a lot squishy in the middle, and the under-pastry had a slightly 'soggy bottom'. The next day it had all solidified and scrummy, yet tasted 'slightly' undercooked. My question is - when I initially cooked it should I raise the temperature to say 160Fan?, or should I lengthen the cooking time? or both?
If I understand correctly, you tried to cook your quiche at 140°F, ie 60°C? That's way too low and would explain why it never cooked properly. Even if that was a typo and you cooked it at 140°C the temperature would be too low.
There isn't unfortunately a unique perfect way to cook a quiche, but generally the recipes will advise you about 45-50 min at 180°C or 30-40 min between 200 and 220°C. Then it's up to you to find the best method according to your oven, the thickness of your crust and the ingredients you add to your quiche. If you add watery elements to your quiche like vegetables, you will need to cook it longer because the water they contain will wet the crust and make it longer to cook.
A good way to improve the cooking is to "poke" (how do you say in English?) your crust with a fork before adding the ingredients, that will allow the excess humidity to escape (it's clearer in this video https://www.youtube.com/watch?v=WMaOd5f6H4Q).
To absorb this extra humidity when you use watery elements in your quiche, you can add some almond powder at the bottom to absorb it (it won't alter the taste unless you really add a lot - I tried a lot once with a spinach quiche and it's actually pretty good!). But the best way to avoid this issue when cooking quiches and pies is simply to use a transparent recipient, like this you can easily control how cooked the bottom is!