Ripe and/or cooked bananas are the devil. If there's one in the same room as me it can make me vomit. I'd rather eat a bucket of sprouts than have so much as a crumb of banana cake and sprouts are the only other food stuff that I don't like. Well, so far, still searching. Thinking about it though, I can't really envisage a situation where it's either a crumb of banana cake or a bucket of sprouts. Surely I'd just have neither?
My wife has exactly the same issue with them. She won't touch them and will leave the room if there's a banana been opened, especially a ripe one. She starts gagging if there's one near her.