i cannot really say much without a link to the site

forget debug. i know where the problem is.

i have seen it once before – when installing the plugin (or were you upgrading something from somewhere ?) the default options are missing.
easily fixed by doing the following:

– goto: wppizza->ingredients.
– select the “options” tab at the top of that page. save that page.

now you will have defaults for that page installed, it should all work now and you should be on your way

thinking out loud here:
there must be some sequence of events (or perhaps some server timeout or something) that causes this . Alas, i simply cannot reproduce this behaviour here so the fix above will have to suffice until someone can tell me the exact sequence of event (version numbers , upgrade from where if any . what was installed first etc etc..)