Help me catch the office coffee thief

[I_am_not_mafia]

If the handle of your pot is black get an ink roller and put black ink all over it then walk away. When you want coffee grab a paper towel. Somebody will start talking about the guy/gal with ink all over their hands. You'll probably catch them trying to wash off.

Instead of blank ink, try Black Death instead.

Or superhot chilli sauce. Once it is on your skin it is really difficult to get off. Washing it won't help that much

I actually have loads myself from growing superhot chillies but you can buy a small bottle of it.

If you get it on your own skin then I found rub plenty of hand lotion on the area first before washing off with soap. The lotion combines with the chilli oil and makes it easier to wash off.