I'm writing somthing for my Japanese class currently, and I wrote 「おいしい食べ物のあるレストラン」and I thought that when ある was modifying a noun you could change it to の but my teacher corrected it to が. Are there exceptions to changing it to のある?
There are restrictions, but they relate to register. In this case の is slightly higher-register than が, but both are grammatically correct. (FYI I think a more natural phrasing wd simply be おいしい食べ物のレストラン.)