After the last peanut incident, I added a rule to mark emails with the lunch menu red when the word satay or nut appears in the body. It’s been working pretty well so far. There is the occasional false positive — “coconut” is a common one — but it’s doing it’s job in alerting me to be careful.

An email filter setup specifies that if a message containing "satay" comes from a specific sender, the text colour is set to red and the message is marked with an alert.