By default the plugin will display items that does not have any term from the selected taxonomy. In this case, if the other items have no categories, they will be included – as in most cases this is expected.
I have turned that option off for you on the Frontend search settings -> Advanced panel: https://i.imgur.com/ESaRkSB.png
I also noticed that you had an category inclusion set to include items from ‘Recipes’ category as well, so it was also including those items. I have disabled that too. In this case, I recommend rather excluding items by categories, which you don’t need: https://i.imgur.com/PR4idCX.png
Now if you select the category, only items from that will be displayed.Best,
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