whenI used to work at BurgerKing (many many moons ago, I hasten to add), my mate mistook mayonnaise for Milkshake mix. We had a few people complain about their chocolate and vanilla flavoured mayonnaise, but on the whole it seemed to go down quite well.
(
thorpe www.voodootrombonequartet.com,
Mon 7 Oct 2002, 12:25,
archived)