No! You definitely cannot feed chocolate to your chicken because it is actually poisonous to them. There is a toxin called “methylxanthines theobromine” within chocolate which is very lethal for chickens if consumed and therefore they cannot eat chocolate at all.
Additionally chickens may not even realize if they are eating chocolate because of the sweetness of the candy it is hard for them to tell.
Therefore make sure you don’t leave chocolate laying around or anywhere they can eat it as it is lethal to them and could kill them.