Such a cool experience!
This is one of my favorite genres, so I had lots of fun, especially with rhymed riddles :) And the overall eerie atmosphere reminded me of Lovecraft stories, very nice.
I must say though that some puzzles were quite tricky and made me do a bit of brute-forcing! But some I got right on my own and it was very pleasant, like the puzzle with the bull or grinded pepper :)
Almost in the end of the game I found a page in the journal that says that every stance is an ingredient :D I guessed so, but wasn't 100% sure that it was the case.
And I looked through the comments to learn about the key, it is pretty well hidden indeed!
It would be definitely great to have some hint system or more impact while obtaining new items or changing the old ones: I sometimes didn't notice that something has already happened, like I got a new ingredient in my inventory without seeing it, and it made the game a bit trickier that it should be, I guess. Maybe some kind of a popup or some sound would help!
I played it to the end and loved it :)