Mine is slightly different. My best experience was about a chocolate bar. A Hershey's to be precise.
The time had come at my son's school where he was going to be allowed off campus for lunch. This meant he could go into the local village and buy his lunch from sandwich shops or the bakery.
Now you know how immature boys can be when they get together. I was so worried that he was going to cause mischief in the village square and I would be receiving a call from the school telling me to come and collect my unruly child.
As it turned out, he arrived home as usual and I asked him what he bought with his lunch money. He had spent most of his lunch money on me. He had seen a Hershey's chocolate bar in one of the shops and remembered me telling him how much I liked them and how difficult it was to find in England. He bought me this and probably didn't have much left over for his lunch.
That is one of my favorite chocolate memories.