To make a good wholesome nun, you need good wholesome ingredients.
After all, if you're making a scrummy cake you need yummy sugar and fluffy flour and all that.
You wouldn't make a cake out of nasty horrid mud and sump oil and things - not unless you're my mad Uncle Tony, anyway, and to be honest it's been many a year since any of my family have accepted an invitation to tea from that mad bastard.
Cake or nuns
Whether it's cake or nuns you're into, finding the right ingredients is essential.
Fluffy baa lambs
Toffee fudge ice cream
Warm toasty log fires
Basically, all the stuff in the world can be split into two distinct categories - good stuff and bad stuff.
Good stuff is what you find in puppies, flowers, chocolate and that sort of thing.
Bad stuff is what goes into axe murderers, wet rot and Celine Dion.
Therefore, in order to make holy nuns rather than evil ones, you need to make sure that they are made out of good stuff, rather than bad stuff. That's simple then, yes?
A bad apple
Well, hang on, it's not as easy as that. The problem comes in determining what is or is not 'good stuff'.
It's fairly easy to tell the difference between, say, a good apple and a bad apple - the good apple is nutritious and tasty and nice, whereas the bad apple is sour and rotten and full of maggots.
Likewise, a good squirrel is clean, sociable and looks after its nuts, whereas a bad one may be mean tempered, deceitful and distinctly wanton in the nut department.
A good boulder
Wild snarly rabid dogs
Old chewing gum
Any movie featuring Nicolas Cage
Slugs and things
Unfortunately, one of the main ingredients in nun manufacture is granite, and that presents a problem.
How do you tell the difference between good granite and bad granite? You see, a good boulder is inclined to just lie around in a quarry somewhere and not really bother anyone.
Trouble is, this is exactly the same sort of behaviour you'd expect from a bad boulder. By and large, bad boulders aren't teeming with maggots, and they are rarely ever reckless with their nuts, so all the normal indicators are of little use when determining whether it is good or evil.
There has to be a way, therefore, of screening the raw material, and this is accomplished by dissolving samples in solution and exposing it to various sinful temptations.
Even so, the process is not one hundred percent reliable, so when the completed nuns finally roll off the production line they are surrounded by armed marksmen and subjected to a variety of further tests until the requisite level of piety can be established beyond all reasonable doubt.
They are still monitored after they are released into the community, reporting for a thorough service every 5000 miles to ensure that there are no traces of residual nastiness.
Raw, unfiltered naughtiness
Keen observers will note that this process inevitably results in concentrated quantities of discarded evil stuff and raw, unfiltered naughtiness.
Officially, this satanic debris is sealed in caskets and buried in consecrated ground. However, rumours abound of darker uses, and the Catholic Church has refused to comment on claims that it possesses missiles with evil warheads, which are kept in a permanent state of readiness and trained on Baptists.