They mix them in large iron kettles with giant ladles over a wood fire, while chanting incantations.....
"Fillet of a fenny snake,
In the cauldron boil and bake;
Eye of newt and toe of frog,
Wool of bat and tongue of dog,
Adder's fork and blind-worm's sting,
Lizard's leg and owlet's wing,
For a charm of powerful trouble,
Like a hell-broth boil and bubble.
Double, double toil and trouble;
Fire burn and cauldron bubble."
Nah... yea, they use TPA, FA, etc.