There are lots of questions about where/how to store encryption keyes, peppers, authentication tokens and what not on a server. They usually get half hearted answers or get closed as duplicate of some other question on the same topic.
I think a canonical question would be in order, and there is already a good candidate: Where to store a key for encryption?
However, the question has some drawbacks. It is focused on encryption keys, but could be more general to concern all server side secrets. And there is some confusion regarding hashing versus encryption that distracts from the main point.
Would it be OK to edit both question and answers to make it more to the point? E.g. make the question broader, and remove the whole hashing thing. Is it even a good idea to use this as a canonical question? Would it be better to ask a new one?