[Alas Babylon!]

Adrenochrome?

That comes from the adrenal gland of a LIVING human. A corpse won't do!*

So what poor living victim did the witch have it extracted from?

*Hunter S. Thompson, from the movie Fear and loathing in Las Vegas

[ROCKLOBSTER]

So what poor living victim did the witch have it extracted from?

Probably the same children she eats as part of her diet.