Soldiers in Iraq with a sweet tooth have the same problem, but now thanks to some schoolgirls from Wales, they can munch chocolate whenever they want.
Chocolate normally melts at 37 degrees, but it's much hotter than that in Iraq, so the girls added a secret ingredient.
They discovered that if they melted the chocolate and added something called glycerine it didn't melt until 52C.
The girls - all from Afon Taf High School in Ynysowen, Merthy Tydfil - are now hoping Cadbury's might help them make more chocolate for the soldiers.
Originally they were working on a school project to look at how chocolate affects us, but changed their minds when they found out about the soldiers.
But you won't be able to buy their creation yourself because under EU rules the ingredients mean it can't be sold as chocolate.
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