Password recipe

I would like to be able to change my password generator's recipe. I know that there is a way of doing this, but I cannot find it. I'm especially interested in changing the default recipe--but also maybe be able to change it for an individual website that's not accepting 1Password's suggestions, and then easily change it back.

1Password Version: 8.10.40
Extension Version: Not Provided
OS Version: Windows
Browser: Firefox; Chrome