I HATE mayo. It makes me gag. If I buy prepacked sandwiches, I have to spend ages checking they don't have mayo in them. I can't eat anything that's even been near mayo on a plate. Ditto coleslaw or potato salad or anything coated in mayo.
The worst is salad cream, though - that's kind of like a runnier version of mayo we have here in the UK, I don't know if they have it elsewhere - it was a standard thing at school lunches when I was a kid, and their salad cream was really runny, and you weren't allowed to choose whether you wanted it on the plate or not. Also, my mother had a taste for eating tinned salmon with chips (i.e. fries, home-made ones) with tons of salad cream, and it was all I could do not to actually be sick being at the same table watching her eat it.
Mustard I used to not like, but I got a taste for it a few years back. Has to be English mustard, though, not that yellow goop that passes for mustard in the US (sorry, guys, but you really have to try Colman's if you want real mustard... )
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