I was four times in a Denny‘s restaurant on my roadtrip in west USA and I got sick two times after I ate there. The only thing that is really GF are the 3 types of „Sizzlin Skillet“. The fries are marked GF but are not or not always. Once I had a Caesar salad and they brougt it with croutons. On the menu the salad is marked GF! I also mentiond that I am celiac and after I told the stuff about the croutons they just pickt them away and returnd me the salad, cause it came back after less than one minute.