Even for non vegetarians, MSG (monosodium glutamate) is a pretty cool addition to the kitchen toolbox, just order some and start experimenting!
Do some controlled ones, for example split a portion into two, ask a 2nd person to sprinkle some onto one of them and try both of them and guess which one has MSG on it.
Do some controlled ones, for example split a portion into two, ask a 2nd person to sprinkle some onto one of them and try both of them and guess which one has MSG on it.