bring some chilli powder, which isn’t readily available stores.
So I get a Sam’s Club size jar of chili powder and put it in my suitcase, and then of course completely forget it’s in there. Customs X-ray in Heathrow flags my suitcase because it, and they are asking if I had a large powdery substance. I forgot it was in here until they took me in the back room and started unpacking everything.
Thankfully they let me keep it and didn’t throw me in prison.