I genuinely don't know what if anything I should do in this situation so will go with a majority vote.
I have a new work colleague who is originally from India. She is vegetarian according to the Indian tradition, which excludes eggs as well as meat and fish.
But she eats pasta, which, as far as I know, usually includes eggs.
I am not in the slightest bit bothered whether she chooses to eat eggs sometimes, every day or never, and I know that it is really none of my business.
However, she is generally very careful not to eat egg- for example always checking the ingredients list if someone brings in cake or biscuits to share. This makes me think that she may genuinely not know that pasta contains egg.
So, what would you do? Would you say anything? Should I assume she does know and has chosen to make an exception? If you were inadvertently breaking a personal taboo, would you rather have it pointed out to you or remain in ignorance?