It was the formulae for the health and mana potions that required the correct ingredients - drawn from the five elemental groups of air, fire, earth, water and pizza. You didn't actually get to make freaky Dr. Jekyll/Mr. Hyde pizzas until QfG5.
Hmmm, that makes me want to play QfG again...
And hungry.
Of course! I mean, I know game designers try to make everything intuitive, bless them, but I like actually having some idea what I'm doing.