Wins Bet With Customer, Gets Written Up

So I worked in a 24/7 burger joint for almost four years(I left less than a month ago). I was able to pull seniority on almost everyone and had used that to get on morning shift on the weekends, which were nearly always dead until about 11 am.

So one day a customer, called C, comes in and sits at the bar while I'm talking to the guy on grill about nothing in particular.

C: Excuse me, what is the spiciest burger you have?

Me: Probably the new Sriracha Burger.

For the record, Sriracha is spicy, vinegary ketchup and it is gross.

C: What comes on it?

Me: (Details toppings) But I don't think it's the hottest thing I can make back here.

C(raises eyebrow): Oh, really? I'll bet you $5 that you can't make a burger so spicy I can't eat it

Idiot Me: Done.

So I cut up some fresh Jalapenos, get the sauce we use for the "Jerk" burger, add some Sriracha, pepperjack, and raw onion. It's not impressive, but it's what I have. I figure the customer eats it fine, wins the bet and we have a laugh. I have both underestimated the amount of Jalapenos I used and overestimated the customer.

Me(serves Burger): That's what I've got.

Then I go back to work cleaning my station. Business picks up and I forget about the customer as my station gets hit. About a half-hour later, my boss comes over and rips me head off about making the food too spicy for the customers and I get written up.

The guy left me the $5, though.