What is the worst food you ever had at a restaurant?

I went to a Chinese buffet. The food was stunningly average. I decided to try the sushi, which seemed all either vegetarian or with stuff like imitation crab, so I thought it would be safe. I bit into what turned out to be a “tuna roll”—it was CANNED tuna. So it just tasted like salty wet cat food with rice.

My aunt went to a pub that served pizza—plain or with sausage. It turned out to be canned dough, ketchup, Velveeta slices and the sausages were cocktail wieners.

I went to a diner with a friend. He ordered plain toast. It came to him with mayonnaise on it. He complained and they told him to scrape it off and eat the toast anyway. I swear I think they just hated him. Who puts mayonnaise on toast?

What is the worst menu item or culinary experience you had in an eating establishment?