A particular food or dish you tried once and never ate again
Pigeon - I think I gave it two chances, and it tasted okay, but as soon as I saw the head the second time around, I decided never again.
Raw oysters - I will never understand the attraction to raw oysters. It's too slimy and "fishy" for my taste. I tried one from my friend's platter, years ago. Glad I didn't get a half dozen or more, like most people do.
Purely vegetarian Indian food - I went to a Hare Krishna temple in West Los Angeles once, and ate their bi-monthly offering of vegetarian Indian food. It's sort of an open-house for anyone who wants to attend. It's a donation-based event, and the food was terrific for what I donated, but the whole time I kept thinking, "You know what this vindaloo needs? Chicken". Anyway, I love Indian food, and I certainly don't need meat every time I eat, but I enjoy butter chicken and lamb curry too much to pass it up.