I bought a tuna salad baguette from a beach "cafe" in Ramatuelle.
I was really hungry and took a commensurately large bite of the sandwich. I immediately knew something was wrong. My nose and mouth were filled, almost pressurised with a fetid, seemingly sewer-borne taste and smell. I think the mayo had been at too high a temperature for too long a time and Billy Bacteria and his retinue had called round.
A massive gastro reflex ejected the offending matter within seconds much to the alarm of those dining around me. Good innit how your body prevents the ingestion of BAD stuff.

