You are welcome!
I think it's possible to add a similar dropdown. As a test I've added a drop-down to the settings list with “bay leaf” and “chili” in it, and it appears it's filtering correctly: https://i.imgur.com/jljigjW.png
You can edit or remove this box on the Frontend search settings -> Custom fields panel: https://i.imgur.com/TMXy04c.png
I believe you can edit this box to add more ingredients you have. I don't actually know how the recipe plugin stores the ingredients data, so it might not work 100% correctly, it might show more/less results as expected, but so far if I select “chili” from the ingredients and type in “spagetthi” then no spaggetthi is shown, but if I type in “chili” the Yum Yum chili comes up – so I'm guessing it's correct.
Before you jump in, this is a very advanced feature, and I recommend reading the documentation on custom field filter selectors first to understand how it works. There is also a video tutorial available if you are interested. I've already configured yours, you just need to enter the additional ingredient values.
Also, please leave the first line untouched on the ingredients selector editor: https://i.imgur.com/nLstwmd.png
It's neccessary, as it creates an empty filter, otherwise all results would be filtered by the first ingredient on the list – giving you incorrect results.
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