The walkthrough only explains how to get one ending.
Look, I know that the other ending is supposed to be secret, but with how MUCH has to be done to get the secret ending, you should at least provide clues, such as recipes for all the other ingredients, as well as clues that guide players to the secret ending.
There's a giant angler at the window, I made spirit and a fireball, and I still have no clue how close or far I am to the secret ending.